I'm having pain in my gspot after having sex we were protected what can cause that?

Need internal exam: You need an internal exam by your pcp or gynecologist to see if there is an ulcer or other lesions in the vagina causing the pain.

Vaginal pain: This could either be pain in that area or in your bladder. Either way it may be due to trauma related to the sexual positioning of your partner's penis. If you have other symptoms or the discomfort fails to resolve over the next several days, see a doctor and get examined.