Is bleeding after sex a sign of pregnancy

I had sex last Saturday after we got done and I went to pee I wiped and it was fresh blood on the tissue. I haven’t had my period in 8 months due to the depo shot. I’ve bled after sex before in the past but not like this it’s usually little spotting the same day then it stops. I’ve been bleeding ever since Sunday I’m positive I’m not on my period. The blood has been more brown now and I’ve had small clots. I have been taking Maca root for my acne and it has worked like magic but I’m not completely sure if the maca root messes with birth control. I’ve been feeling sick nauseous dizzy headaches only for two days. I haven’t been late on my shots