Low platelets, 119-137 over past few yrs. 10 yrs ago were higher in the 200's. Some bruises when not hurt. Other bloodwork ok. 40 F- Should I worry?

Relax. Usually we never find the explanations for these minor platelets variances. Have it followed yearly.
Low Platelet counts? Platelet counts >100, 000 are acceptable provided there is no other issues present. If your Hemoglobin (Hb) and WBC/Differential count are entirely normal, then there is not much to worry about immediately. But you should get serial platelet counts, done at every 3 to 6 months for the next 1-2 years and do it at a reliable Lab such the Quest labs. Also send us the results of a current CBC. That wil.