Late Period. New birth Control, May i be pregnat?

The birth control i was on they stoped making my doctor prescribed me the generic version of the same pill i took it as directed everyday not one missed pill even took it around the same time everynight. me and my boyfriend had un protective sex fequently( but he never finished inside me always pulled out) I was supposed to start my period 4 days ago but usually i would start 3 days after i was supposed to. and im on the 4th day and nothing not even slight discoloration. but i have been experiencing cramps, back ache normal period behavoir. Do you think i may be pregenate?