Yes, mold is really bad for people with allergies, asthma and eczema. I had an eczema and asthma flare-up this past summer after visiting Austin, Texas where the mold was very high, even though it had been very dry. I don't have asthma flare-ups that often, but I did have one after being around all of that mold.
One thing to try is clipping your finger nails very short. That way, there won't be so much damage to the skin if you should feel the urge to scratch.
Zinc has really helped me. My eczema cleared up after I started taking it about six weeks ago, and I haven't had an eczema outbreak since. Also, it has made me stronger and improved my skin in general. I no longer mind climbing escalator steps or going up a flight of steps when the escalator is out. This is new for me.
Even with zinc, however, I still have to be very careful. One shampoo that is wonderful for sensitive skin is California Baby Super Sensitive Shampoo and Body Wash. When I ordered it, the company sent me a trial size of their moisturizing calming creme with botanicals. When I first tried it, I noticed a fragrance, which concerned me, because I have a lot of problems with fragrances. I found the creme wonderfully moisturizing, though, and thought that I'd give it a try. By the second day, however, I noticed my skin becoming very sensitive, so I immediately stopped using that moisturizing creme. At least I've learned to pay attention to these early signs of potential problems ahead.
Good luck with the mold tests. I think you may be onto something that what may be causing your problems is environmental. That may explain why all of your symptoms came on at once.