Vaginal pain

I'm 17weeks + and I've been experiencing a lot of pain and pressure this week in my vagina with cramps in stomach and back. Went to the doctor the other day to see what's going on. Cervix is closed, baby's heart is beating, & no UTI. What the heck is going on? Anyone else going through this? It hurts so bad. It almost brings me to tears. Vagina hurts when I'm sitting but even worse when I'm walking. Let's not talk about going up the steps... Idk what to do.