Hi,
Welcome to the ehealthforum and I am really glad to help you out. Your concern is regarding the status of your pregnancy.
Pregnancy occurs only during the time of ovulation. Ovulation is the release of a single, mature egg from a follicle that developed in the ovary. It usually occurs regularly, around day 14 of a 28-day menstrual cycle. The ideal timing of intercourse in order to conceive is day 10, 12, 14 and 16 (in case of late ovulation) of a 28 day cycle. If you had missed your periods and had intercourse around ovulation, so chances of pregnancy are there.
You can test at 9 or 10 days past ovulation with a sensitive ( 20 - 25 mIU ) pregnancy test. Aimstrip pregnancy test gives good results and can detect 20 mIU of HCG.I sincerely suggest you to do a urine for pregnancy test and if the test comes negative, then please wait for your periods and repeat the test after 1 week of your missed periods date. You can also get your serum HCG levels checked.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care.