I m a 20 year old boy nd i have two girlfriends , they both are best friends nd i have sex with time to time, is there any chance of HIV ?

Unless you want to be a daddy, you should be using a condom anyway. So practice safe sex and use a condom. Condoms are not 100%, of course, nothing is - but at least they are the most effective way of preventing HIV, pregnancy and a slew of other STDs. Most importantly, do not tick them off. That's more dangerous than anything else right there - ticking them both off at the same time. We womenfolk can be vicious little things when angry.