Hi, I had gone through your question and understand your concerns. In most cases this is sign of uroinfection or kidneys stones, and even if you had sex recently, this is rarely a sign of STD. This is mainly self limiting and doesnt require any specific treatment and you should just be patient and have fluids to promote urination. Less likely it may indicate possible bleeding in urethra, bladder or kidneys from popped vessel or some other cause. IF this continues you should do urine analysis, urinoculture and kidneys ultrasound to rule these main causes out. You should drink raspberry tea and plenty of water till you do tests. Also, avoid sexual intercourse and have keep good hygiene. You should reduce salt in your diet as well since this could lead to increased risk of urinary stone formation. Hope this answers your question. If you have additional questions or follow up questions then please do not hesitate in writing to us. I will be happy to answer your questions.