I would definitely recommend going to see your primary care doctor
about this issue right away. It sounds like you are having fairly significant symptoms of genital discomfort, and your doctor can help you figure out why.
There isn't any sexually transmitted infection that would cause "instantaneous" burning sensation upon having sexual intercourse. Most sexually transmitted infections require a few days or weeks to really begin producing symptoms, which might include a burning sensation with urination or the development of ulcerated areas that burn. HPV does not typically cause these symptoms. However, both chlamydia and gonorrhea may cause burning with urination. Herpes may cause the development of small painful blisters or ulcers on the genitals.
Instantaneous burning sensation with sexual intercourse may also occur if the skin of the genitals are inflamed or irritated. The vaginal fluid is acidic, and this could cause some discomfort of there are active areas of fungal infection, eczema
, or other skin conditions.
Regardless, the first step is to go see your primary care doctor for a good examination. They can help figure out if this is a sexually transmitted infection and, if so, what you need to do to help clear it up as quickly as possible.