Just a note to start - no one here are doctors.
You can get some STDs from unprotected oral. You could get gonorrhea, NGU, syphilis and genital herpes type 1. Syphilis and herpes would result in sores, so that doesn't sound like what you have going on here. Gonorrhea could change the odor of your urine, as could NGU (which is an infection in your urethra). NGU can be caused by normal mouth bacteria entering your urethra during oral sex.
The dried mucous could be a discharge, or dried semen or something. If you've only seen it once, I wouldn't overly worry about that. It could be something from the oral sex that you missed before you put the condom on.
You should get seen by a doctor. This could also be a urinary tract infection, which is not an STD. In any case, a doctor who does some testing will be the only one who can diagnose you.