What was in the roundworm treatment? If you have the container, it is written on it. If not, was it a yellow liquid?
Over the counter dewormers are OK depending on the active ingredient.
Is that ok? Or do I need to take her to my vet...I'm very worried I love this kitten and I hate seening her sick
Piperazine if fine. It has been around for a long time and is quite safe. Follow the label dosage and instructions.
Another good drug is pyrantel pamoate (Nemex and other brands), but there is no reason to change to this. I'm naming it for information only.
After the kitten swallow the eggs, they hatch into larva. The larva burrow through the intestines and migrate through the body. Eventually, they end up in the lungs and are coughed up and swallowed. The swallowed larva become adults and start to produce eggs. Some larva form cysts and stay in the body. They rarely do harm, but will reactivate during pregnancy and stress. This is how they get passed on to other cats. The drug does not kill the migrating larva, which is the reason you keep seeing worms even though you've already worms. The second dose killed the worms that were still migrating.
I usually recommend that people worm kittens 4 times at about 2-3 week intervals. It was fine to repeat the first dose in a week, but you should be able to go a bit longer before the next doses.