I Have Pain In My Left Shin Bone. The Vein

I have pain in my left shin bone. The vein on top of it feels swollen when I touch the sore area with my fingers. It is slightly warm over the sore area. The leg doesn't appear to be swollen, and there is no visually apparent lump but I can feel one with my fingers. I'm not experiencing leg weakness. It seems to feel a little better when I rub and massage it. It almost feels like a mild vibration that coincides with the pulse. It first started yesterday when I got out of bed. It isn't bruised or red. Yesterday when I was putting my leg in different positions to alleviate the pain, I felt mild pain over the buttock of the same side like sciatic pain. It stopped when I switched positions. I have always had poor circulation in my legs but, only minimal spider veins and of yet no varicose veins. Any help you could give to me to help me figure out what this is could be would greatly be appreciated. Thank You, Tracy