What is your problem with that? Many people make mistakes.
She had regular sex with one guy. That isnt unusual after the first experience.
I would bet she is practicing abstinence now.
Abstinence works.
I've never heard any speculation about how many partners either of them had. They were sexually active. Period. Just like many other teens. I wouldn't assume much beyond that.
After the first time its not such a big deal and a lot of fun to boot. There's not much compelling reason not to go all the way with a new boyfriend if the first relationship goes sour. I am amazed at how early kids are sexually active.
If she's not sexually active now, its probably because she's not dating and exhausted from taking care of her baby. It just ties in with the agreement with the (Candies?) shoe sponsor for now.
I'm not judging her. She made her own choices and is living with the consequences. She took a chance she wouldn't get pregnant and it didn't work out that way. She's done nothing heroic or particularly unusual. As I said before, she should just slip into obscurity and be the best mother she can be to her child while developing an appreciation for having a loving family. Role model? I think not. Credible abstinence spokesman? I also think not.