My biggest complaint right now is my skin color is changing dark and skin is usually irritated
Skin is getting darker because of the higher pressure. Once you hit 10inHg and beyond, you're pulling a lot more blood from the lower part of the skin to the upper layer. Try not to be under the vacuum pressures for too long and switch over to SSJ more. SSJ and edging can help to push the iron radicals out of the skin faster.