Do I need a new battery

Here are the facts:
I have a 2014 Chevy Sonic. I've had no issues with her until this week.
Monday I gave a neighbor a jump but didn't drive my car all day after.
Tuesday morning I needed a jump myself. Car wouldn't autostart, just kept
clicking instead. Got a jump, drove for half an hour.
Wednesday I ran several errands with no issues.
Today (Thursday) She turned on fine, but the stereo display wouldn't turn on.
But she did play music, even with the display off. I thought it was weird, but
she was running and I had a doctor's appointment to get to. I drove there,
parked, and turned her off and on again and everything was back to normal,
display turned on. Hours later I got off work and it was the same as Tuesday.
But after I stopped trying to turn her on the stereo turned on. Key was in my
hand, not ignition, and the driver's door was open, which should turn music
off. Couldn't turn the music off.
Anyway, I got a jump and she immediately turned back on. I didn't need to
wait a minute or anything. The anti theft light came on this time, but it's off
now. I drove about five minutes, made a twenty minute stop, then couldn't
start her again to get home.
Do I need a new battery? I read it might be related to the keyfob, or the
antitheft system, or the stereo is possessed and is draining the battery. But
my coworker who gave me the jump tonight is on team new battery and says
a bad battery could be causing all that.