Nadine, I would test as well just to put your mind at ease as Sam said.

My SIL didn't find out she was pregnant until she was 20 weeks! She continued to get AF like clockwork and the only sign was that she put on weight. She was already a bit overweight so it wasn't noticeable that all of a sudden she had a tummy. Eventually she went to the doctor for a check up and found out she was pregnant!!