I seems you have an sexually transmitted disease
Their are various types of sexually transmitted disease and all have some commons stuff while some things are different,
1) If discharge is " grayish white or yellow and has fishy smell" its mostly bacterial vaginosis
2) If discharge with pain during intercourse
3) If discharge is yellow-green, itchy, frothy, foul-smelling probably trichomoniasis
4) If discharge is white curd like its probably candidacies,
5) If pain/ burning while urination its Urinary tract infection
So its can't be determined from your description alone as too many possibilities as listed above,
Consult physician whom you are comfortable talking to (mostly a female physician I guess?)
Here is mostly what they will do.
1) do an visual inspection of your vaginal area
2) collect some sample for laboratory test
3) may be some blood test
if they have suspicion of systemic infection
4) may ask for testing for "HIV" (Mostly depends upon where you are as its recommended in USA to ask patient for that test - PLEASE DO NOT BE SCARED - ITS JUST A LEGAL FORMALITY IT DOES NOT MEANS YOU HAS AIDS/ HIV and should not be a reason not to take medical attention for present problems, if You wish you can deny the HIV test
5) lastly they will treat it will some ANTIBIOTICS.