I took my second cycle of clomid (clomiphene) in the beginning of july. i still haven't got my period. can i take a pregnancy test now?

Yes: Yes, it has been long enough now that if you conceived from that Clomid (clomiphene), (clomiphene) your pregnancy test would be positive. If it's negative however there is a chance that even with Clomid (clomiphene) you did not ovulate. In that case you would need a course of progesterone (i.e. Prometrium) to get your next menses so you can start again.