What Precautions Need To Be Taken After Having Unsafe Oral Sex?

I had unprotected oral sex (gave and received) with a man who I just met. There were no obvious signs of broken skin, rashes, or blisters on his mouth or penis. We did deep kissing with tongue and he rimmed my anus for about 2 minutes. In addition we did a lot of petting. I have never had an STD and would like to know the risks associated with this type of sexual encounter.Should I be tested for any STI s and which ones should I be worried about? Thank you.