Bloating &gases without causes for >week ,pelvic cramping, mood swing &no changes in breast ,we had sex on 10th,11day are these signs of pregnancy?

If you had have had: sex and there is no barrier to stop pregnancy- like birth control pills/condoms, then yes you might be. Get a pregnancy test to be sure then see a doctor asap to verify everything is in order with you and your body to prepare for a health pregnancy.

Not likely: If you had your last period, then these are not likely symptoms due to pregnancy. Pregnancy symptoms don't usually begin until after you miss your first period. But, do take a HPT if you miss your period.