Do you mean you received protected oral twice? Did you also have protected sex? Did you give oral?
If you received protected oral, there is a very small chance that you could get genital herpes type 1 and syphilis.
Syphilis isn't that common, and your partner would have had to have a sore in their mouth to transmit it. You wouldn't see symptoms of this for 10-90 days, but the average is 21 days, and you'd get a sore called a chancre. This doesn't cause burning, pain, discharge, etc. You can test for this at 6 weeks. If you get symptoms, but test negative at 6 weeks, test again at 90 days, and get to the doctor as soon as you see symptoms.
If you don't already have herpes type 1 (think oral sores, like cold sores but not canker sores), then you could get genital herpes type 1 from receiving oral sex. This can happen even if the person performing oral doesn't have a sore, but it's more likely if they do. The time from infection to symptoms is usually 2-12 days, but the average is 4 days. You can test for this now, and then again at 4 months to make sure you don't have it. If you test positive now, it's a pre-existing infection that you had before this encounter. About half the adult population has this, and 90% don’t know it. Ask for a type specific IgG blood test.
You used a condom, so the chances of either are reduced greatly, and the chances of getting either are lower with oral sex than vaginal or anal sex. It's up to you whether to test or not, but I probably wouldn't bother. If you haven't tested for awhile, it might be a good idea, but there's no reason to run out and test. The chances are really low.