late period

My husband and I have been TTC for 7 months. I had my IUD removed and things went back to normal (average 26 to 29 day cycles, never longer than 29). This month though I'm on cycle day 31 but still getting BFN. What is the deal? Can something be wrong? Has anyone else experienced this? Obviously I want to get a BFP but I'm more concerned about health issues than anything. If it's a baby time will tell, should I go to the dr or will they just tell me to wait?