I'm 11 days late. had a yellowish discharge with a streak of blood in it... but still no period today?

My man and I had on the 12th and 17th so it is still too soon to check by the piss test. Doctors told me so. Told me to come back monday if I still have no period. Probably to do a blood test. Thought my period was going to come today as I had the yellowish almost mucus looking discharge with a streak of bllod. Then about 3 hours late a dab of blood in the same kind of discharge. are tender but that can happen on an impending cycle also so I cant rely on that. Have pressure almost like cramping in my uterus area and my loins are sore. What do you guys think? Am I pregnant? I have been regular for quite a while now. Cycle every 3 weeks. Now I am 11 days late.