AIO by being sad over my boyfriend's response?

I'm having a bit of a rough day today. My mom has schizophrenia, and she goes through cycles of being worse and better but she is always in at least a low level of psychosis. No one is able to get it under control, but it's been REALLY bad the past month or two. She lives about an hour away, but texts me every day, and the texts can be pretty upsetting to read.

It's somehow getting even worse. Yesterday I woke up to horribly disturbing texts from her, then went to bed after reading even more creepy texts that she sent in the middle of the night, then woke up to another really upsetting one. I won't get into the content, but trust me, they're bad.

On top of that, I had an awful nightmare last night about becoming schizophrenic myself, the hallucinations were terrifying, my mom was there and seemed happy that I joined her, etc. I woke up pretty upset afterwards and just really wanted a hug from my boyfriend.

I texted him that this morning. He responded with "I get off at 1:30". I asked if I could come grab a hug really quick after work, he said no, that he has stuff he needs to do that won't get done if I'm there. I'm confused as to why telling me when he gets off work was his only response when he would not like me to do anything with that information anyway? I told him yesterday I wouldn't be available this evening because we're doing Easter dinner tonight, since I have to go deal with my mom this weekend. I just needed like 10-20 minutes in early afternoon.

I just had a strong reaction to that, idk. I was already pretty upset but that made me cry quite a bit, I'm not sure why that was the breaking point. Am I overreacting because I was already upset? He has a right to want time to himself of course. It's just an emotional day.