I have discomforts when urinating what could be the cause?

I already googled some informations but cant say what is probably wrong with me..these are my symptoms: mild burning sensation during urination and a little"scratchy" feeling internally under my scrotum (i assume its part of the tube that conducts the urine) the color was not too dark i 'd say more yellowish than the usual..no swelling in any part no external pain or tenderness and i dont feel like peeing everytime and i noticed sperms are sometimes present but I took antibiotics the day after and sperm problems are gone but still have minor burning sensation when urinating..what do I have?