When you have ringworm it tends to itch or burn but with Lymes disease, if your already showing round spots, you have probablly already experienced sore joints and felt weaker. Also Lymes Disease rings dont spread as rapiddly as ringworm. Lymes Disease can also have what is called a bulls eye, a circle with a dot inside of it. Although the best thing to do is consult a doctor.
I have never heard of Lymes disease having spreadable circles. It usually only presents as a dark circle with a lighter area in the middle resembling a bullseye. Some mistake it for a bruise. You can get multiple light colored circles with ringworm as the parasite spreads.
Ringworm isn't a parasite it's a fungus like athletes foot or jock itch and as it progresses it will spread. It will typically heal on its own in about 3-4 wks with otc anti fungal creams or sprays, if it lasts longer than that you can get a anti-fungal script that will heal ringworm after about 3 days or so..although, you have to find the cause of it, which lots of times is pets, especially cats and dogs, but can also be in the soil, and on plants and can last up to 12 months, with ringworm there is usually itching or burning, but with lymes there isn't...(usually)...and the bulls eye rash that appears doesn't mean thats where you were bitten by the tick, and lymes is a very hard to diagnose disease, because of all the diff. diseases that have the same type symptoms..