I too went through a similar issue earlier in the year. DO NOT PUSH IT IN THE GYM!!! Trust me it will only make it worse, as you risk over extending your energy reserves and getting sick much worse. I tried to work through a cold PCT and ended up with pneumonia - losing a full 3 weeks. PCT your horomones are a mess, which has to compromise the immune system to some extent. Absolutely no reason to risk it. Just try to keep calories as high as possible if you can.
Don't know if it helps but I always find massive amounts of Vit. C (5+grams a day) help to get rid of a cold sooner.