After having intercourse i got really light headed and tired, not the usual, and i know he let himself loose inside. could i be pregnant?!
Am I Pregnant?!
Assuming you had sex at the right time of month, it takes about 7-10 days for an embryo to implant and then a few more days to a week before you get a positive pregnancy test. There is no way you would have symptoms immediately afterwards, there have to be many changes first and an increase in the hormone produced by a fertilized embryo.
But to answer your question- if you are having unprotected sex, yes, you could be pregnant. Regardless of how you feel afterwards.