I am in my third trimester of my pregnacy and me and my parter had sex and there was blood all over us both. We don't know from who it was from though. I know while being pregnat you can spot after sex so i thought it was me, but the second time this happened he was the one bleeding. Im figuring the blood was from him the first time this happend. We didnt use protection and im scared and wodering if I could catch an infection or std?