I Have A Lump Or Knot On Eyebrow Area Only

I have a lump or knot on eyebrow area only comes out when I bend my head down swells out really big when I bring my head back up couple mins later it goes away been to several doctors they can not figure out what it is could it b due to sinuses had a mri done it came back normal I have severe migraine headaches could that b due to that