I am very worried I am experiencing frequent urination and

Patient: I am very worried. I am experiencing frequent urination and pain in my lower back and in my groin area. I have been to my doctor and he said I had prostatitis. He prescribed me doxycycline hyd. I’m concerned because I have been on the medicine for two days now going on my sixth dose but the pressure or uneasiness in my back and groin area are still there. Also the tip of my penis has some discomfort to it. Am I panicking or do the meds need take time to take effect? I’m scared that it could be a std of some sort and am scared. Reading all the webmd info points that I may have gonnahrea. Could this be?