Hello, and I hope I can help you today. First of all, I want to assure you that your symptoms are not normal and you really do need a physician visit for full evaluation. However, what may be causing the stinging and what may appear as something white at your vaginal opening may be a vaginal yeast infection. Yeast infections, or infections of the vagina with the fungus Candida, are extremely common in women. They are not transmitted by sex, but are caused by overgrowth of the normal yeast that lives in a woman s vagina. This overgrowth can occur due to hormonal imbalances, hot and moist conditions, or can occur after sex. Yeast infections produce thick, cottage cheese appearing discharge which may actually appear like chunks of white cheese coming out of the vagina. They also usually present with redness, itching, and burning of the surrounding vaginal tissues, which may be the reason why you feel burning when you try to urinate. However, there are other possibilities that could be producing similar symptoms. For example the sponge you see at your vaginal opening could also be a foreign body or remnants of a tampon if you have placed anything inside the vagina recently. Burning with urination can also occur due to infections of the bladder or other urinary tract sources. For this reason, it is important that you visit a physician, preferably a physician such as a gynecologist who performs pelvic examinations. Untreated urine infections can spread to the kidneys and cause severe infection, sometimes requiring hospitalization. So it is important that you have an accurate diagnosis promptly to avoid any further complications. I hope that I was able to adequately answer your question today, and that my advice was helpful. Best wishes, Dr. Brown