Is this common in endo or is it a sti/std?

I have this painful redish patch just at the entrance of my vag. It only hurts during sex. I looked online and i havent seen any connections to STIs/STDs but I looked up the endo part and seen some images that looked similar to mine but just not at the entrance. Please help, What is this ? !

image

i have this exact thing im going to the gyno on monday! I can let you know