I need help

I (21 year old female) have the most random question that I'm hoping someone could help me answer. About two weeks ago I finished ovulating and right after the day after it had ended I noticed some brown discharge with blood in it and that whole day I had cramping, nausea, dizziness and I felt tired.

During these two weeks I've been feeling slight cramping and I'm normally a nauseous person but more recently I've been feeling a little extra nauseous. I'm now two days late and normally I don't worry about being pregnant but this time I am a little concerned. I've already taken two pregnancy tests but it was the cheap ones.

My husband and I have always been careful but there were two incidents in which the first one we played with each other but didn't even noticed until we slowly woke up so it was while we were asleep so we don't know what really happened that time. The other time we did it without noticing it was on my highest day to conceive but we still used protection.

So what do you guys think it is? I would go to a clinic but I don't have insurance and we're a little short on budget