Dampening the immune system

Recently (well the past year or two) I think I may be suffering form an overactive immune system, I've been getting a lot of autoimmune responses such a skin rashes etc. Also I haven't been ill in all that time, just every few months I get a bit "run down" incredibly tired and a bit achy for a week or so and then it goes as quickly as it came on. I also never feel completely refreshed, not exactly tired but getting up never feels good no matter how long I sleep for.

Now obviously I'm going to see my doctor about this but I'm wondering if there's anything else that I can do to manipulate my immune system into being a little bit less aggressive or is there some other possible cause for this? Sorry that this post is a bit glib and thanks

Any possible new allergens introduced? Food change, pet, move or anything.

None that I can think of at all. Started when I was at university and has persisted now that i'm back home. I've seen a doctor a couple of times about my rashes, they first thought that is was empytygo but it doesn't spread like that and the medication for it didn't work. It was then considered a bit of a mystery for a while and then another doctor (who was a skin specialist) said that it seemed to be a form of eczema, but the eczema creams don't seem to be very effective :/

I've never had this kind of thing before so I'm just a bit concerned that things might be not quite right with me