What Causes Tightness To Breath, Cough And Neck Pain?

hello, i was diagnosed with hypothyroid and very high level of allergy last september 2010. since then im an medication including thyroup, and telekast-L. the problem is that if i dont take telekast-L even for two days consecutively, there is tightness in breathing,persistant cough for about 1/2 hour with thick white discharge, some sweating, some pain in neck. it also leaves me with some pain in the lower ribcage area. what can be the real cause of the breathing difficulty? allergy or the thyroid? what should i be doing to correctly address this problem? need ur advice urgently. thanks in advance.
T.R.O