What causes petechiae on my legs and feet to come and go? i've had this occurring for the past two years now. small, pinpoint reddish-brown dots appear on my legs/ankles/feet/beneath feet. heat? multiple cbcs done, all clear. doctors say it happens?

If you are overweight, that may be a partial explanation. Keeping legs dependent may cause venous stagnation and can result in petechiae around hair follicles. For healthy diet: http://www.choosemyplate.gov/., exercise 30 minutes/day, drink enough water daily so your urine is mostly colorless, have safe sex, no tobacco alcohol weed or street drugs. Get HPV and Covid vaccines. Wish you good health