Bleeding after sex

OK so I had sex last night with my boyfriend ND after we got done I went to go pee and I had blood smeers on my panties ND when I wiped I had bright red blood. Has anyone ever had this happen before? I'm not on my period I just got over it about a week or two ago. It didn't last long when I woke up it was gone. If this is not allowed in this room please point me where to go. This is the first time it's happened and I got scared. Is something wrong with me?!