How To Treat A Swollen Red Big Toe?

Hi, I have a swollen big toe on my left foot. I have not injured it that I know. I had lost my toenail 6 months ago and it is nearly back again. The bottom left hand corner of it seems to be the worst part. It is very red and swollen, not that hot, I can bend my toe without pain until the swelling limits it. I have been doing a lot of walking around (on holidays) lately. Any ideas??