My LMP Was April 4, Then We Have The Deed

My LMP was april 4, then we have the deed las april 21, but no penetration really occurs and he didn't ejaculate. Since it was my ovulation week, I got scared and took nordette 25 hours later then the other 4 12 hours later. Its been 10 days and no withdrawal bleeding yet. I have 28-30 days cycle, and if its right i should have my menstruation this may 4. Is there a chance of regnancy? Thanks!