Hmm... Another vitamins question from me. Cut down on my vitamin B complex tablet, been sneezing all day?

[Chellebells]

I cut down on my vitamin B complex tablet, cut in half. Now I didn't have the best of immune system, and would often get colds and allergies play up. Since taking the B vitamin, I haven't had a cold or allergies play up. I cut down, and I've been sneezing all day and low energy. Could this be related? Think I'll go up back up to one tablet.