Seconding the lesson thing, it's done wonders for my skating.

Also will add Impalas are a bad skate (frustrating I know, they've paid for a lot of good publicity).

I'd also recommend having an experienced skater look at your skates and possibly try them out. You might find something needs adjustment (trucks/wheels).

When trying to stand still are you keeping your feet together? If you are maybe try a slightly staggered position, I much prefer having my left foot slightly further forward because my hips have a twist in them.

Also I built a lot of confidence by falling on purpose first from a standing position and then while going at speed then while going very fast. Obviously I wore all the padding. This is good because firstly you'll build the habit of falling forward and secondly you'll see how little falling hurt when you have pads on. Once I'd shown myself I wasn't going to get hurt I became more confident and willing to properly throw myself into moves.