Since you asked if you were, yes. You are being paranoid. This would never be how someone gets HIV. HIV is transmitted in very specific ways and they include unprotected vaginal or anal sex with penetration or sharing IV drug needles. That's it. Air and saliva inactivate the virus. I WILL say that, dude, why scoop semen off floor with your finger and lick it? Not sanitary. I'm sure you are fine but really, think before you do things like that. HIV is not an issue, but it's still gross.