Hi Felicia,
You have a small itchy lesion on your left calf.
You have not described any increase in size, not any change in the color or shape of the spot.
Based on your limited description, I do not think that this is cancer, and definitely it has not "spread everywhere". So please relax.
However, I would advise you to go to a doctor if only to lay your mind at rest. A visit to a dermatologist is actually a lot less stressful or scary than you imagine!
If you think that any spot/mole is turning cancerous, the worrying symptoms that you should look out for are "ABCD": Asymmetry (irregular shape), Border (irregular edges), Color (uneven color across the spot), and Diameter (size more than 0.6 cm, or that of a small pea).
All the best, and God Bless!
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