I gave birth October 11th and my period came 17th November till 27th November and i apparently ovulated 1 st December and i had sex unprotected and my period is due 15th December and i took a test yesterday and it was negative.. could i still be pregnant??

I had some clear stretchy discharge that people said meant i was ovulating.. did i ovulate later than expected??

Im not breast feeding and my period is 2 days late