What Could Fever, Congestion And Mild Nausea While On Birth Control Indicate?

Hi I ve had a small fever, congestion, burping but no heart burn, headaches , mild random nasuea and have been gassy for the last couple days. I am a 20 year old female, on tri-cyclin lo birth control, I take it within the same 4 hours every day. I am sexually active with the same partner.