My boss hurt my feelings so I quit but I regret it now?

I just got an amazing job 2 weeks ago. Everything was going well ( So I thought). And my workplace is really big on the NO GOSSIPING rule. ITs a new manager at this location I got hired at, so its me and a few new girls. Well, Last week, A new girl came to work for her first day. She was sweet, I liked her. And she fainted. (long story short she went home)So me and my coworker were continuing our work and just happened to talk about her. It slipped out of my mouth I said oh maybe she was

Nervous. I DID NOT mean it in a negative way or to gossip. MY boss found out and he FLIPPED out at me. He kept knocking me down. Saying How frusterated he was and I should never gossip at work. I HONESTLY did not mean to gossip. Why would I gossip my first week at a new job? Then he said I never communicate with him either ( text him how work is going ) he preceeded to bring in my trainer, so she gave me more constructive critisim, How I ask questions without putting in effort to figure it out

my self first which is NOT true whatsoever. I felt like he just kept knocking me down. He then said he could fire me cause he has so many interviews lined up. Basically, he said next time we talk he will either thank me or fire me. ( My trainer will now be monitoring me and will report back to him). So I was scared to even go back, thiking I would get fired. I texted him the next day politely saying I felt like I was getting in trouble for no reason, and decided to resign. I now regret it.

the reason im upset is because it was an amazing job opportunity. It was in the medical field which would help me in medical school. I was only there for 2 weeks. I was just so mad that my trainer would give me constructive critism that was not true.. I cant stop regretting this feeling.