I told my boss I wasn’t going to be able to work as much during the fall because of college and I think I’ll lose my job.

I politely informed her by email ,as well as requesting a day of for a medical appointment. She didn't accept my request, she's been weird and even rude towards me AND I saw a job opening on indeed. The position was for reception and I'm a physicians assistant. However, one of the girls from reception used to help with assistance. Needless to say, as soon as she was rude I started looking elsewhere and sending my resume. The atmosphere is questionable at best. The first red flag was Too much gossip and complaining. The second red flag is this one. I'm not waiting for a third red flag. I have a second job and there's a lot of openings. It's so frustrating that you can't even ask for a day off work without risking your livelihood. I'm in a comfortable position, but not everyone else is.