Why after me and my husband have sex, my vagina is irritated? Recently got checked I do not have an STD or anything like that. My pap smear was normal

Second opinion. May want a second opinion. Irritation may be seen in other medical conditions or medication use. If you are using spermicides or certain condoms it is possible to have an allergy which can cause irritation. One common reason for sex to irritate the vagina is not enough lubrication. You can buy lubricant at most pharmacies.
Vaginal dryness. Poor vaginal lubrication is a common cause of this. Trying using a lubricant like astroglide or KY jelly to see if this helps.
Dr. Can evaluate. Sex should not be painful. Pain during sex could mean an infection, an anatomic problem, endometriosis, or possibly vaginal dryness. If you are experiencing burning and pain after sex (called dyspareunia), you might consider seeing your doctor to evaluate if there is a problem. If you are using condoms, this may be the first sign of a latex allergy.