Strange Rash on Chest, Back, Neck and Legs

Sometimes after I come back from a walk, or when I am stressed I break out in a huge rash on my body that itches like crazy its really annoying. I'm just wondering if anyone here has experienced that?
My hair loss isn't that bad, slight recession of the temples nothing really noticeable, but I want to prevent further onset of MPB. I have always had a big forehead and I'm not just in denial like so my other people on hair loss forums have said to me like "Your just in denial about your receding hairline" as I type this there are pictures all round my home of me from I was young and my foreheads pretty big so its always been a fivehead but whatever its the way it is. Some people have small foreheads I have a big one lol. Anyway what I do to prevent my hair loss is I wash my hair either everyday or every other day and I use shampoos in rotation to keep my scalp in good shape. One day I will use a Salicylic Acid Shampoo (good at clearing the scalp of dead skin) and the next day I would use a Ketoconazole based shampoo ( very good for greasy hair and allegedly good for MPB) I also have a Tar Blend Shampoo which consists of Cade Oil, Pine Tar Oil, Peanut Oil and 1% Coal Tar extract all these ingredients are beneficial for scalp health and to prevent dandruff which can't hurt. I have a Kent Military Brush made with pure bristle some people rave about bristle hairbrushes that they increase scalp circulation. I don't it seems to make my hair greasy, so I tend to use it to brush my hair before washing it. I feel it helps to release sebum onto the surface of my scalp so it can be washed away.

Internally I try to eat well my diet consists of eggs, lettuce, chicken, turkey, olive oil, onions, peppers, spinach , carrots, mushrooms, bacon, occasionally beef. I don't eat bread or pasta at all never have done. I have Oatmeal or porridge as I call it every morning for breakfast never had a problem. Oats are the only grains I eat. I try to stay away from junk food but its hard it can be addictive. And I take milk thistle everyday.

What do yo u guys think?

Hello, do you make your porridge with water or milk? And sugar?

Just oats and water for the porridge. Can't stand milk and sugar first thing in the morning.