Stomach heavy tight and gassy under alot of stress felt since july 4 had intercours july 3 (last 2 mins) then period started during. Am I preg?

Unlikely. If your period started on time and was normal you are probably not pregnant. If in doubt, check a pregnancy test and, if it is negative, repeat it in 3-5 days to be sure. Stress is notorious for exacerbating IBS which can cause bloating and this may be what you are experiencing. Hope this helps.