Did you mean to say it wasn't protected, or it was protected?
If it was protected, and the condom stayed on the entire time, and you didn't lose your erection with the alcohol, you're fine. There is a slight chance of getting herpes, syphilis and HPV from skin contact where the condom doesn't cover, but for such a brief time, I wouldn't worry.
If it wasn't protected, there is a chance you could be infected, even if it's just a couple of minutes. Obviously, the longer the encounter, the higher the chances, but there is still a chance here. You could be at risk for gonorrhea, chlamydia, NGU, mycoplasma, syphilis, herpes, HPV and HIV.
You can test now for gonorrhea, chlamydia, NGU, mycoplasma and HIV.
Herpes can take up to 4 months to show positive on a test, and syphilis can take about 6 weeks - 90 days. Syphilis is uncommon, so if you don't have any sores, and test negative now, I wouldn't worry about retesting later.
There is no test for HPV in men. Symptoms, if you get them, may not show up for several months.