I started feeling mine move around 15 weeks it really just depends on how big you are. You won't feel them move pretty much everyday until around 22-24 weeks and even then some days they dont move around all that often. Some days they go through a growth spurt and are tired and dont move around other days they are hyper it really just depends. Try not to worry about it I know its hard but in a few weeks your baby is going to be moving all the time! :)
From previous posts I have read, it is totally normal to not feel the baby for days when you are this early. I am almost 19 weeks, and I have not felt any movement at all yet. But I am not worried, the HR is great, and the u/s tech always tells me the baby is very active. My uterus feels very "unstable" if that is the right word. It is a very weird and uncomfortable feeling, like if it was a hip joint, I would swear it was about to dislocate. I am contributing that to the amount of activity going on in there, I just can't feel any kicks yet.