I have no idea what is going on

So last night my boyfriend and I were doing stuff and when I got up because we were about to have Sex we looks down and his hand is full of blood and I have bloods everywhere. It looked like I started my period and so I cleaned him up and I cleaned up and put a tampon in and when I got home I took the tampon out and it looks like that stage you get when you just end your period and it’s all brown and stuff. I haven’t bled since and idk what this means. My period was suppose to start on the 30th but it is irregular so I have no idea. I know I’m not pregnant because we haven’t had sex in 3 months and we didn’t even get to have sex last night