Do you take any? Do you think they work?

Although I try I know my diet isn't perfect and I've been feeling a bit run down lately so wondering if I should take some multi-vitamins or some other supplement (like olive leaf extract maybe?).

Any suggestions on brands to try, I walked into the chemist this morning and was completely overwhelmed lol!
Oh and also I have trouble swallowing big pills (they seriously make me gag ). Is there such a thing as a multi vit that isn't the size of a brick?

TIA!