Iam feeling an intense burning sensation in the vagina just after coitus, without condoms. takes one hour to settle, what could be the problem?

Common: What you describe is very common. Sometimes it's due to a yeast infection, so you might want to make sure you don't have that. Other times it can be due to vaginal dryness... Only you know if that's the case. Make sure you're well lubricated either w/ foreplay or lubricant. Some women suffer from a condition called vulvodynia. Stewart's the v book is a great reference for this.

Lubrication: Most of the time vaginal pain after intercourse is caused by a lack of lubrication. Try using astroglide or another sexual lubricant. Ask your partner to spend more time with foreplay before proceeding to penetration as well.