I was diagnosed with Hypothyroidism & Coeliac disease around 2 years ago & currently am on 100mg Levothyroxine. I now seem to catch every virus going & when I do it completely knocks me down & takes me weeks to get over it. Currently have a really bad cold, in its 10th day now & I feel worse now than when it started. Is my immune system just completely knackered? Any hints & tips out there?