I Am Female 55 Years Old. I Have Hypothyroidism That

I am female 55 years old. I have hypothyroidism that i take medication now for years. recent blood work is ok except for low iron which is common for me and i guess i should take supplements. blood pressure tends to always be on low side. headaches tend to be an almost daily thing and was told i probably have cluster and sometimes visual migraines. very fatigued all the time three episodes in past two months of severe dizziness with vomiting and headache, had to keep eyes closed to relieve symptons. went to emergency did bunch of motor skills tests and blood work said caused by headache. your opinion please. I read symptons may be low iron, vertigo or related symptons. had a brain scan a year ago all fine. ekg done about month ago fine, but do get occasional flutters or heart jumps it seems. .....sick of being sick and tired