Could The Symptoms Of Pain While Urinating, Itching, Discharge, And Pain During Erections Be Signs Of An STI?

I had unprotected sex with a girl, after that, I ve seen symptoms of an STI which I m not so sure of. Ever since then, I ve had pains while urinating, itching of my penis, random discharge (milky) from my penis and serious pains when I get erect. Sometimes while I m asleep, I get erect and feel so much pains and when I wake up, my penis is erect and slightly curving to the right with a milky discharge at the tip of my penis. Please help