My first post here...looking for some help with my game

I started out playing sngs on full tilt 3 months ago as a foolhardy player at the 50+5 level, losing most of the time, but winning every 5 or 6 games and keeping even. I quickly dropped down to the 22s and 11s with more success. I was making good reads and felt like I was playing very well. Lately, my game has all but dropped off. I've found that most of the players that get ahead in these games and end up ITM are those that take big chances (eg., calling an all for half their stack with AK, AQ, KQ, JJ) and I know these arent correct plays unless you have a very strong read on the player. I find myself getting nervous when I have a strong preflop hand, and even postflop if I hit top or even two pair. In many of these situations I wont even bet, pre or post-flop, as I'm scared I'll get trapped or have a big raise put on me. Does anyone have any tips I can use to improve my game and get over this? I know (or hope, rather) I have the skills to beat, or atleast be a winning player at these lower levels. Thanks in advance