Marks outside of vagina. Does this look like its from tampon string irritation or sex?

Sexual health
1

I'm really not sure if these sores were from tampon irritation and scratching or from sex? Has anyone had something like this before?

2

https://imgur.com/a/l9zyPHK

3

cant say ive ever had the tampon string do that. do you have long nails? maybe cut yourself whilst changing tampons or scratching. id see a doctor in any case