cls350sam

Hi im new on here and was wondering if someone could advise me on a problem which I have occurred. My car is a CLS 350 CGI 2007 automatic petrol. I have only owned the car for 2 weeks. I recently thought it would be a good idea to dismantle the wood panel around the gear knob so it could be wrapped. I unplugged two wires which connect to that panel. I also took the wood dash trim off to be wrapped, doing this i had to disconnect a few wired to do with the heating vents.

After doing all of this, my car occurred a flat battery. The dash computer did show a message but soon disappeared so didn't clearly see what it said.
I managed to jump the car and left it running to get a charge into it to drive home.

The next day I was about to pull away at a round about and my car suddenly went into limp mode. i pulled over and turned the car off. The car came out of limp mode but the engine management light stayed on. After a few hours the engine management light went off.
The problem didn't occur again for a few days then suddenly happened again.

Last night after driving for 20 mins the car went into limp mode, again i stopped and pulled over, restarted and then happened again 30 seconds in.

I rested the car for about 2 hours, 5 mins into driving it went into limp mode twice in 3 mins. This morning i drove the car for 3 miles and no problem, but engine management light has stayed on.

Any ideas what it could be?