What Are The Chances Of Getting Pregnant Without Penetration?

I was with my boyfriend on Friday evening. Friday was also the second day of my period, so we decided not to have vaginal sex. All the same, we still got a bit intimate. He released precum while we were having oral sex, but majority of it was swallowed. After that, we grinded a bit, and his penis was touching around my vagina. Again, it never entered me, and I also had a tampon in the entire time. I do not know if more precum was released between the oral sex and the grinding. I also can not be sure if all the precum was swallowed. Since precum can contain sperm, I am now terrified of conceiving from this. Considering these factors, do you think I have a good chance of conception?

I am also stressing out because I have no way of accessing any sort of emergency contraceptive, such as plan b. What can I do??