I had an mri done if my cervical spine and they put minimal cerebellar ectopia measuring 2mm should i be concerned? base of neck has been swelling with bad headaches?

Likely unrelated: The cerebellum structures are usually contained within the skull but occasionally the cerebellar "tonsils" are found a slight bit below the level of the skull. The 2 mm reading is well within the 5mm maximum used to describe this benign condition of "ectopia". In without other findings in the report it is normal. You should clarify this with the doc who ordered the study.

Recommend: Your MRI films are not worrisome, and show a congenital variation (mild Chiari). This is NOT the cause of your headaches, which could be migraines, tension headaches, or even caused by jaw or dental issues. Suggest seeing a neurologist.