Have u used a different brand of towlet paper other than what u have been using?
When you say you have a burning sensation, is this on your genital area all the time, or is it when you urinate?
You may have a urinary infection and the urine could be too acidic causing the burning sensations.
And like BluCrystal says you may have an allergy to what you are using. Only use non-biological washing detergents, wear cotton underwear and do not use soaps, shower gels, feminine sprays in the genital area. You can use gentle non perfumed soaps or anything that is suitable to use on babies.
You may even be allergic to the latex condoms if you use these. Ensure that your sexual partner uses latex free condoms.
When you say the doctor checked you for yeast infections, I presume this was for candidiasis and thrush as well. Thrush can cause itching and burning, so I am surprised that no yeast infection was found. I also presume that you got checked out for bacterial vaginosis and had your urine tested?
As a home remedy, apply natural live yogurt to the area where it is stinging. This will cool the stinging down and draw out any inflammation. Do this for a few days until your symptoms clear up.
Hope you get relief very soon.
Best wishes.
This could be anything from the toilet paper you use, soap, laundry soap used on your panties, tampons, menstrual pads, douches, and even sex if your partner is not as clean as he should be. I think you should see a doctor about the possiblity of your being over-sensitive to something like this. Blessings - Blu