Newby to the drone world and taking baby steps hoping to keep my drone in one piece.

Here's what happened.  I'm still in beginner mode.  I took off using the home location return choice and was flying ok when the low battery sounded.  My drone immediately went to the safe height but then instead of returning to the take off point it started flying away out of my yard.  I fought to bring it back and succeeded in keeping it in my yard. Every time I tried to bring it down it would get to 4 feet from the ground and immediately shoot up to the safe landing height. After 3 tries I decided to grab it when it was low enough.  I got it in my hands and could do nothing with my controller.  I tired quick pressing and holding the power button on the drone but this did nothing.  The drone was indicating on the controller that the power was at maximum so I set the controller down and reached in carefully and removed to battery pack.

Suggestion are more then welcome and in my opinion quite needed at this point as I know I panicked a little.

Retrieve the TXT file for the flight from your mobile device, upload it using these instructions, provide a link to it in this thread and someone may be able to tell you why that happened.

When you takeoff, you should not fly away until you know that the home point has been set and really check the map to make sure it is actually correct. It seems to me that the home point was not correct.
When you realised that the Mavic was heading elsewhere, you should have cancelled the RTH. On the screen there is a big red X and a flashing message pointing to it to cancel if necessary. If you had done that, you could have manually flown it into your back yard to a few feet high and then just tapped the landing icon so it would land for you.

Flipping the sport mode switch will cancel whatever it is doing too.

Next time this happens, if it ever happens again, turn off the downward sensors in the app and try again.

My recomendation, as you are starting. Before take off, and if you dont remind to see the HOME POINT HAVE BEEN RECORDED. Go to menu and press the Home point, to define a new one. I usually do that before start.

about a month or more ago i was taking a walk around a tidal wetland area with my dogs and drone. My first battery was at about 50 % so i used it to check my settings and fly a bit. Then i loaded a fresh battery and started my walk with the intention to land it wherever i was when the battery got low.
on my first battery i went through proper return to home steps and acknowlagement from the app that home point was updated.
The 2nd launch i took off fast (did not wait for home point update as i intended to land it somewhere else)
When i was about half way through my walk at about the furthest point from home base my first battery warning came on - i decided to fly a bit more before landing. Before 10% i started bringing it back to me. At first it worked but then as my battery went critical it strongly kept flying away from me.
The message kept saying "aircraft landing" which i could not have because there were many pools of water and it was not being responsive to my commands.
Then i decided to put full throttle down - rather a crash land in the water even, god forbid, but that seemed a better option than let my drone fly off to somewhere else i had no idea where it was going.
i tried to crash land it in an area that that was about 200m ahead of me - but as it was still moving and i was running through puddles and over rough terrain it was difficult to keep my eye on it.
Eventually i lost sight but ran to where i thought i saw it last - but it was nowhere to be seen.
The light was fading, the tide was comming in - i plucked up the courage to look in the water pools and ran up and down the long grass hoping to spot it - no luck.
My car was about another 200 m further. I decided to get my dogs to the car before continuing my drone search.
When i got to the car and loaded my dogs and was trying to calm myself to decide on the best plan of how to find my drone, i looked down the path where my walk had started and there it was - i could not believe it - i did a double look and it was still there - i still cant believe my luck on that occasion.
My take away from that experiance has been to make sure i do proper 'home point updates and wait for home point confirmations' before i fly.
My other takeaway from that experiance is that i do not wait to use up so much of my battery before landing - i now want to land my drone before i get to 10% critical level.
Summary: before each flight ensure proper home point update - this will be a voice message and a green notice on screen ( if you do not see or hear it, land the drone and start the launch again) - no need to reboot drone and rc.
When you take off - do so vertically at first to a height about 10m at a steady pace (not high speed) - this gives time to do final home point updates and take landing spot images - then u should be good to go - but be sure to hear and see the message that home point is successfully updated.
Land the drone before critical level battery kicks in - unless it is directly above yr head and you are 100% sure that your home point was updated and that it will land where you are but better yet land it before 10% - thats what i think and how i deal with it - good luck..