no period in 35 days

I have a question my hubby and I had sex on my most fertile day and since my last period 35 days ago I have been experiencing nausea, cramps, motion sickness, and wanting to eat but nothing sounding good. my cervical mucus around my "period time" was still cervical mucus and it had a brown tint to it plus some spotting. I have taken an at home pregnancy test and they came back negative. I am going to the doctor to schedule a blood pregnancy test tomorrow. but could I possibly be pregnant or what else could this mean?