This is the abbreviation of "amına koyayım" in Turkish. This q letter sounds like k, and we Turkish guys say this directly as aq. In English "amına koyayım" means, fuck it/you sth. But of course it is more coherent in Turkish.
Turkish people are also use "aqmun". This is very hard to explain if you don't know any Turkish. So I will use this form of aq in a sentence and you guys see.
am = cunt, pussy... koymak = to put ... k and q is similar pronounce... AQ is put it in your pussy... stick it(whatever it is) in your pussy.. But generally, after every word, means "fck this shit."