STDs/STIs symptoms within 24 hours - possible?

[BerniePerkins]

Hello everybody! Thanks for reading this. Well, I hope my question isn't rude or something. I just created this account because I seriously need "peace" in my mind. I'm ignorant when it comes to medicine so please forgive me if my question doesn't make any sense.

I'm a male, 21 years old. I had sex (to be more specific, vaginal sex) for the first time 4 days ago with my girlfriend. It was my first sexual experience so far. We didn't use condoms or lubricant. I was nervous so we stopped after 5-10 minutes. After this, we decided to try oral sex (with condom this time), then I just masturbated and ejaculated normally.

My problem is that after ejaculating, I started feeling "uncomfortable" down there. I mean, my penis didn't hurt or anything, I just felt uncomfortable.

4 days have passed and I still have this "uncomfortable" sensation down there. It's not painful, I can live with it, but it bothers me, especially when I'm trying to sleep. I also have burning and "cold" sensation sometimes (especially at night when I'm trying to sleep), but only for a few seconds. Also my discomfort isn't permanent. It only lasts a few seconds, then goes away, then it comes back for a few seconds and again, goes away, and so on.

I checked my penis and it looks normal/healthy.
I don't feel "burning" when I urinate. The burning sensation happens randomly and is not permanent.
My girlfriend says she's healthy, she even showed me her blood/urine tests. Like I said, I'm ignorant when it comes to medicine, I don't even know if a "normal" urine or blood test reveals STDs/STIs but she said she was fine.

Thanks for the replies!

[Life360_Dave]

Hi, no std shows symptoms the same day but takes about a week for them to appear which would be a white puss penis discharge and burning while urinating. Yours is most likely an injury from the act itself or even masturbating.