Feeling like you can't control the ball is frustrating.
Improving takes patience and time - your improvement is based on the quantity and quality of your practice. Spend twenty minutes each day on ball handling - the website coaches clipboard has fantastic drill ideas - and remember two keys to good practice:
1. Keep your head up - if you are training with a partner, have him/her hold stand a few feet away, and tell them how many fingers they are holding up while you do the drill. If you are training alone, pick a point on the wall to stare at or try to count something in the distance.
2. Push yourself - dribble as quickly as you can. Messing up is encouraged! If you can do the drill without mistakes, you need to speed up or find a more challenging drill.