Delayed Period

Good eve. I am now one week delay ,I had my menstruation last Nov. 14-21. We are using condom as our protection. I was a bit sick for a week last Dec. 1-5 guess, took bioflu and neozep for a couple of days. The next week I had suffered toothache, I took mefenamic acid to aid the pain for about 4 days. Pregnancy test also tested negative. Should I be worried about being pregnant?