Hello

if its sting and all then she need more lubrication because I went through this before and theres nothing wrong of having more lub.. However just have her relax a bit and she will be a bit more aroused to it. And no it will not stop her from getting pregnant

She could have a urinary tract infection. She needs to see a doctor right away. If she has one, she will have to take antibiotics.

My fiance and I used to have this problem early in our relationship. Defianently get some lubricant. It makes things so much easier and a lotl ess painfull.

Are u using latex condoms? If so she could have a latex allergy...
You might have her go to the gyno just to rule out any possible infections