Pregnancy - Second Trimester

My books and a few friends have stated that I should feel the baby around 14 weeks. Well, I haven’t felt anything yet. There are times when I thought that I felt the baby, based upon descriptions that it should feel tingly or like butterflies. Unfortunately, those feelings that I thought were the baby aren’t there anymore and didn’t last more than the one time. I feel like I am missing something now that I am at 18 weeks and still haven’t actually felt the baby moving inside me.