The sad truth is, bad things happen to good poker players. It isn't a time to question your faith, but with every loss, it is a good time to question your play. Below is a spectrum of short-stack all-in scenarios against a small field, listed from worst mistake to "couldn't be helped."
Moving all-in only to find you are drawing dead. If this happens to you, there is no getting aound fault on your part. You misread your opponent. There are cases when you have second to nuts and are up against a very unlikely nuts, but chances are you were just nuts to think you were ahead.
Moving all-in with bottom pair. You probably thought your opponent was bluffing, but since this is a loosing scenario he probably wasn't. Misread again. Even if you read correctly and moved in on the flop, your opponent is likely to have plenty of outs to put your life at risk.
Moving all-in in a race situation. Most likely this means a pocket pair (88) against two overcards (AK) pre-flop. This move should be avoided when you are high on the hog, however the low stack needs to take a shot at doubling up. If your opponent does indeed show a race situation, it could go either way. You shouldn't feel blessed or robbed.
Moving all-in with a high flush draw on the flop. Why would I consider this a move to feel better about than the race? Well, you can't be sure you are betting into a race. If your opponent has a good poker face, you could be moving in against pocket rockets. When you have A 9 of clubs and two clubs hit the flop, you can be sure your draw can beat anything your opponent currently has (unless the board paired.) Also, I'm assuming there is a significant amount already in the pot from pre-flop betting that you want to protect/steal. While your odds of winning are under 50%, the odds are a known quantity. With a little math you will know for certain if you made the right choice.
Moving all-in with an over-pair or top pair post-flop. You are likely ahead even though your relatively small all-in may get a caller on a good draw. If your opponent out draws you, take comfort in knowing the hand was played well.
Moving all-in with the current nuts. Whether this is preflop (AA), on the flop or on the turn, you know you are ahead. The only thing to worry about is your rival's small number of outs or possibly a runner runner. If you lose here not only did you not make a mistake, but it is likely your opponent did. Remember this and take his or her money next time.