Yeah I thought I ordered the smallest one but it fits me snugly lol

it's really just preference, I think some get it looser so it will fit their baby longer/older, I got mine as small as I could but when she grows out of it, If she still needs the amber I'll just get her a new one

Thats what I real and it touches the back and side of her neck but goes a little low in the front. I've seen babies with tight and looser ones so I wasn't sure

well it works best when the amber is in contact with the skin, the body temperature warms the amber which releases the oil and is then absorbed by the skin