What Causes Severe Itching With Discharge In The Vagina After The Intercourse?

i am a female, and sexually active. it has been over a week since my last intercourse. About 2 days ago my urethra started itching and I have strange discharge from where i urinate. It's white but alot, and if i clean it up, it comes right back. It's very red and painful. It's embarrassing to keep itching and I don't want to tell my boyfriend but i'm scared to have sex again without knowing what it is. Any suggestions of what to do or what it is?