Confused! 43 day cycle

I went off birth control at the beginning of June, and had a normal 31 day cycle for 3 months. Now all of a sudden I'm on cycle day 43 and still no period. I took 2 pregnancy tests. I thought I saw a faint line on the Clearblue test, but First response looks quite negative and I know it's supposedly more sensitive. I am about 16 DPO and just so confused. I'm not sure if my cycle has just not regulated yet after going off the pill or if I may still be pregnant, or if something is just wrong with my body/cycle and I need to go see a doctor. I haven't had any pregnancy symptoms. I am abnormally hungry the past week but I've never heard that as a early on symptom. Any suggestions/commemnts? Anyone in the same situation?