If i only been on the nuvaring for less then a month and had unprotected sex is there a chance i could get pregnant?

Always a chance: In a word, yes. There's always a chance you can get pregnant even with any contraceptive therapy. No method is 100%. It is always recommended that within the first month starting a new contraceptive that you use a back up method because any hormonal contraceptive therapy takes at least a month to get fully established. Of course I'm not saying that you got pregnant but there is always a chance.