I just developed three small, pinprick & pinhead sized spots on my right breast. the spots are covered with a reddish brown scab or crust looking surface. what could it be, and is it concerning? does inflammatory breast cancer cause such spots?

It is not feasible to provide a meaningful opinion without additional history, physical examination and may be some tests. What you described is a cause for concern and it would be prudent to see a doctor. Wish you good health!

These would not be signs of breast cancer. They could be insect bites or inflamed tiny hair follicles. See your MD or a dermatologist if more if these lesions appear.