I almost started crying at work. I want the next school semester to start.
I'm sorry to hear that. What made you almost start to cry at work?
I'm sick of working with my boss.
Its better to let out your emotion than to hold it in. If you felt you were about to cry then you should have gone to a private place and cried. Hopefully talking about the situation was enough to make you feel better.
I'm still upset.
It's reasonable that you're still upset. I think in the future you should let your emotions out, instead of holding them in. Holding them in isn't healthy.