I have burns in my vagina during my period and when I have sex

i had a urinary tract infection, and then it got better. Then it came back, the doctor told me I had vaginitis. But it continued for the next month. During the covid, I went to the doctor every month and they couldn't do a test to know what I had. I tried all the creams I could think of, canesten and all the other things I could think of. I have noticed that my noises come when I am menstruating and all the time I feel something uncomfortable. And then it goes away but it always comes back every month. No, I don't have any other discharge that I've noticed besides blood. And moreover, during my sexual relations it hurts and burns. I don't understand, what's wrong with me?

No, I haven't tried any lubricating cream, can you buy it in a pharmacy or does it have to be prescribed by a doctor? And, I don't use soap with perfume the only one I use to wash myself is cetaphil because I have sensitive skin. Thank you for the advice, it's really nice!