My husband and had a unprotected intercourse on dec. 16 and 17 2013.. I am 28 day cycle and my last period was dec. 05 2013. . And I experience spotting on my 15 day which I never experience Before. . at this mOment I had dz bleEding buT nt heavy like a nOrmal period. .

You can be. Since you are married are you not having sex more often than just a couple days a month ?

There is a chance even with protected sex . But there is no way to tell at this point. You will have to wait and see if you have or miss your regular period.