Why has my big toe been swollen for over two months now. what should i do?

See your doctor: This is a problem that requires a face-to-face meeting with your doctor. In that meeting, your doctor will listen to you, perform a throrough examination and possibly order labs or other tests. Based on this information, he/she will be able to tell you what's wrong and what to do about it.

Many possibilities: Including, trauma, infection, arthritis or other underlying condition. See podiatrist and have examination and x-rays and get a diagnosis.