Yes, being cold can make me worse. Others on these forums have reported the same thing. You are not alone. Aids that have worked for me:

-- hot showers
-- switch to warmer clothes like long sleeves or thicker pants
-- brandy. not kidding
-- hot tea. regular or herbal
-- pacing and squats to warm up from within
-- eat a snack if it's been awhile since I ate
-- heat water and swish in mouth if I don't feel like drinking anything (my jaw can get tight)

I guess we could categorize those as:
-- add warmth (from an external source)
-- create warmth (internally from your body)
-- trap warmth

Basically as someone with TOS, you have to manage your warmth more than a non-TOS person.

HTH