can't stop overthinking/overanalysing (pls help)

I am 'dating' someone. In the beginning I told him I didn't want a relationship (because I had just gotten out of one) so we became friends with benefits. Now it is almost half a year later and we have been seeing each other frequently and I have feelings for him.

I'm pretty sure he doesn't have feelings for me (he doesn't ask many questions about me, still dating other woman, he told me he is very picky and he is not super affectionate). Tho I like to convince myself he does actually like me... because he also gives signs he actually does (ask me to go on a trip in summer and asked me out to have dinner).

So I need to tell him I have feelings for him. We were supposed to meet tomorrow but he had to go home because his cat died. I asked if he was coming back to town and he said no, I will be back on monday. And I replied 'ooh'. I got hurt he forgot we had plans and last time I saw him he even reminded me about it. So then he replied 'damn, we were going to have dinner. So stupid of me'. And he asked to reschedule.

So this was two days ago and ever since I have been feeling super anxious. And I keep seeing if he texted me and thinking 'how long should I wait to text back'. Before everything was fine and I wasn't that worried about it. I guess I really got my hopes up since last time I saw him because he started texting me more and opening up more. Now I feel him pulling away again.

I have exams and I can't even study because I feel so distressed and hurt about it and just keep thinking in loops. Thinking 'does he like me or not?'. I know its not healthy but I can't stop.