Soy Oil in Selenium Supplement - Cause of Muscle Pain At Night?

I'm still learning about everything hypo and only just got a prescription from GP for levo, had BH blood tests which indicate Hashi's.

So, in my quest to get me feeling good again and in anticipation of levo, I am like most people on here, looking at diet (harsh GF) and taking supplements to get levels good, if not optimum. Though not to the extent I am over dosing

I already take B12 complex, C and Zinc, and have added D3, K2 and B12 (bought online and checked the quality). But at the weekend I picked up some Selenium from the UK high street Supplement outlet. I took this with evening meal and have had leg muscle pain at night from hips right down the back of leg - last night woke me up.

So I checked the labels only to find that the selenium (absorbable) I picked up in town contains SOY BEAN OIL, and the label also states contributes to 'normal thyroid function'. Am I being over reactive or could that be the cause?