What would be the cause of a reoccurring warm sensation in my calf. sometimes it's is also just a feeling there. not lumps, bruises, my leg looks norm?

What you describe: may be what we call a "dysaesthesia". This is a sensation we perceive that doesn't have any obvious cause. Pain from an injury is NOT a dysaesthesia b/c there's an obvious cause. Dyasethesias are often caused by inflammation, pressure or overreaction of the nerves that send impulses from a specific part of the body to the brain. Determining a specific diagnosis or cause requires a medical eval.