need advice and opinions

I  have been on the pill four five months and was on the first week of a new pack of cilest pill i missed three days then doubled up then stopped taking it completely i then got a one day withdrawal bleed what is not the normal for me if i miss a pill I had unprotected sex  before i stopped the pack then started getting cramps in my lower stomach could that be ovulation ? on that same day i had unprotected sex i still havent got a period  could i become pregnant due to this