Some kind of nematode looks like.
Try pyrantel pamoate. It's called "Pin-X" or "Reese's Pinworm Medicine." It is for pinworms, but if you look up the molecular mechanism of action of pyrantel, it actually works on all organisms in the Nematoida phylum. This particular medicine is largely confined to the gastrointestinal lumen, so it isn't absorbed well into the rest of your body. This means it will only work on parasites within the digestive tract. If you think you have them elsewhere, you will need a different medicine that is only available through prescription (or in certain animal dewormers. The reason why I am suggesting to try pyrantel pamoate is because it is one of the only anti-parasitics you can get for humans over-the-counter.