There might be a slim possibility of a yeast infection
, but that's almost never a problem in men
, even though antibiotics sometimes trigger yeast symptoms in women. You have not yet been treated for trichomonas, which could cause urethritis--but not blood in the urine.
Except for the slim possibility of trichomonas, which you should discuss with your health care provider, you can be sure no STD is causing whatever symptoms you have now.