I'm on week 6 and I still have problems getting them all in. Mostly I lose track of time, and next thing I know it's bedtime and I'm short a packet or two.
You have to be very careful not to shortchange your packets though - I got thrown into a big stall this week because over the weekend I had a couple days in a row that I shortchanged mine.
What's helped me get back on track is to really plan my packets out for a day - I use the MyMedifast website to randomly pick 5 packets for me per day out of my "cupboard" and I mark each one off as I eat it, so there's no way I get to bedtime without knowing how many more packets I need to have that day. Of course, if I don't like the food it picks, I'll just switch it out for something I do want instead.