I've used Misoprostol a few days ago and I'm still in a lot of pain. Is this normal?

If the treatment were successful, you should no longer suffer any pain, just blood loss. A lot of pain after a few days could mean that the uterus is not completely empty, meaning that there are some remainders, an incomplete abortion. The only way to check this is to get an ultrasound. It is very important that the uterus is completely empty, also in order to prevent infections. Therefore, we advise you to have an ultrasound made as soon as possible to check whether the uterus is empty.
You could say that you think you had a miscarriage. Before you go, though, you have to check carefully with your fingers deep into the vagina whether all tablets have been dissolved properly. If possible it would be better to wait a couple of days, because the tablets don't dissolve easily in the vagina. If doctors find remainders of the tablets they could report the woman to the police. In countries where women can be prosecuted for having an abortion, it is not necessary to tell the medical staff that you tried to induce an abortion, you can also say you had a spontaneous miscarriage. The doctor CANNOT see the difference (unless there are remains of tablets in the vagina).
If the abortion was incomplete, you might need a curettage, also known as vacuum aspiration, during which a doctor will remove remaining tissue from the womb. Doctors have the obligation to help in all cases.