Having fun, but my GF is stressing

I (M23) and my gf of 4yrs (F23) are on sorta a hiccup now.

I volunteered to go on a 2 week work trip away from home and my gf just started school the first day of the trip. She does full-time school and work and sometimes gets about 5hrs of sleep if work and class overlaps on the same days. She’s been telling me that she’s stressed, tired, and mad that I made a selfish action on going to this trip. On top of school, we have a dog and 2 cats at home (the dog is mine and she’s made it clear that she hates dogs).

She did tell me months prior that she didn’t want me to go on the trip, but I told her that I’ll be pocketing at least $1k per diem total and that I wanted to experience something new for work.

I’m having a great time on this work trip. I’ve been going out and hanging out with co-workers, going hiking, and even went to a concert too. I haven’t called her everyday since she’s got a new schedule evey week for school and I don’t want to disturb her while she’s sleeping or doing HW and don’t wanna make her mad about how much fun I’m having.

I just got off the phone with her and she told me not to talk to her for the rest of the trip until I fly out to go back home. She said only text her.

I didn’t realize prior how busy she was gonna be/stressed and really want to make it up to her. I would appreciate any advice or even another perspective on things. I’m supposed to fly back home this friday if work goes smoothly this week. Thank you.