Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Unsure

I used a similar, more expensive product, which led me to this one, but with the previous colostrum product, I felt an almost immediate effect, whereas with this one, not only did I not feel any effect at all, I had some unpleasant somatic complaints, but I am unsure if they are related. I stopped using this particular product but may resume use in the future.