How To Get Rid Of Itchy Spot On Vaginal Lips?

I have two large dark spots and one small one on the inner lips of my vagina. Some times they itch at the top of the lips a little burning. I have constipation which I take meds for but doesn t help very much. The stool at times (realy often) is hard to elmnate so I will push with my fingers on the skin between vagina and rectum to get the stool out. I have tried what my doctor discribes but nothing seems to help. I was thinking maybe the pushing might be the problem. Also I am on blood thinner for A-Fib. Thank you.