Q: Car wont start after battery died and now there's a blinking red light behind the steering wheel

So yesterday I left my lights on all day and when I got off work the battery was dead, no lights on the dash or anything. We used the key to use the shift release on the steering column to get it into neutral to move and jump. It wouldn't turn over but the dash lights came on followed by a blinking red light that's behind the steering wheel and there was a weird clicking noise after trying to start the car. AAA sent a technician and he couldn't get it to start either. We tried having it hooked up and charging today for 20 minutes still nothing but the dash lights and the blinking red light. Any ideas on what to do before I have it towed to the mechanic tmrw? Battery is less than 2 months old. Had a tune up 2 days ago. Absolutely no indication something was wrong prior to dead battery.

My car has 146000 miles.
My car has an automatic transmission.