How far along were you when you had the abortion? If you are having sex then it is possible to be pregnant.

Are you sure the baby was dispelled from your uterus? Did you bleed and pass the baby?

Did you go back for you mandatory follow up session?

There could be a chance that the abortion did not work, which could cause that to happen. IF you went back for your follow up you would know if you were 'clear' or not.

If you were clear at your follow up, then you could be pregnant again.

I did go for my follow-up and they said they could still see something on the ultrasound. They gave me two more pills but I hardly bled after taking them. I have only been having sex again for about 2 weeks now. I'm hoping that the positive is just a result of what may be left that they saw on the ultrasound. I go in again next Friday to see if there is still some stuff left over.

If there is still tissue or products of conception in your uterus, then you really should be advised to have a d&c (surgical abortion method) before it makes you ill. Your uterus will need to be gently scraped or vacuumed free of tissue, especially if the follow up pills are not working properly. I would strongly advise you to make another appointment and get checked out as soon as possible.
Best of luck!
Peace,
Jenn