Is emergency contraceptive pill reliable with obesity?

Hi doctor,

I had an abortion about 5 months ago, which was around six weeks into the pregnancy. About 12 days later, I had sexual intercourse, and my partner ejaculated inside me. I took a Plan B pill that same night. I experienced bleeding for six days after, similar to a regular period, so I assume Plan B worked. I took a pregnancy test around 22 days after taking Plan B, and it came back negative. I had bleeding on next month. My breasts are starting to hurt, which I usually associate with my period. However, I had sex on end of that month, and I got really scared. Even though it was unprotected sex for only 5 to 7 minutes, I stopped because I was worried about the possibility of pregnancy. My partner assured me he was not close to ejaculating, but my anxiety persisted. Two hours later, I bought a Take Action emergency contraceptive pill.

Given that I am obese, should I also consider getting a copper IUD as an additional precaution, even if it is not yet been 5 days since the unprotected sex? My breasts hurt, but I took Take Action. What happens if you take it before your period? Is my breast pain due to my period or could I be pregnant? Is there a possibility of pregnancy even after taking Take Action? I am really scared, and I cannot wait to start regular birth control. I am tired of feeling this fear. I have always been obese, so I am concerned if Take Action will even work for me. I am just scared; please help. When should I take a pregnancy test? After all of this, how harmful is Plan B to the body? Should I consider getting a copper IUD for emergency contraception, even though I took Take Action? I have heard that if your weight is over 165 pounds, Take Action might not work. What should I do? Please help.