child w/ dark circles under eyes

Greetings,

My 4 year old son has developed dark circles under his eyes in the last few weeks, which seems to have coincided with moving his bed into a different room in the house. This new bedroom tends to be more damp (we live in a tropical environment), and i have found, and washed off, a small amount of mold here and there within the room. I am wondering if he is sensitive to any possible mold that might be lurking around?
Along with the dark circles under his eyes, his pecularities are as follows:
sensitive to drafts from the window, turning down foods that he usually likes (though, his appetite seems to still be fairly on track), weeps easily, has a slight clear runny nose alternating with stuffiness, he has complained of a headache from time to time. He has had back-to-back upper respiratory infections for months now, and rarely has more than a few days between illnesses.
Any help is greatly appreciated!