Could Hot Flashes And Delayed Periods Be Due To Pregnancy?

i need help to find out if im pregnant. i have the feeling like i need to puke but it just never comes, i also have like heat flashes i guess you would say, where i just get really warm and kinda sweat. i don't pee alot during the day, but as soon as night rolls around i need to go like every half an hour, my last period was on Feb 13th-16th 2011 ans it is now aug 10th. if have no idea what else i need to know