Swab test

Ok so I'm having a few swabs done at the doctors tomorrow as I think I may have an infection down there, it's definitely not an sti or anything like that as both me and my fiancé are completely faithful, we're also trying for a baby. I'm worried they'll find an infection that will cause us problems for having babies though. Worried a swab test will hurt too, I struggled with a vaginal exam when pregnant. I'm so nervous 😔