184 is fast enough for luck not to be such big factor... But then again if you are saying you have 184 there should be much more shares in in this time. There must be something wrong. But there are more possibility.
1. You stop mining
2. Internet went out for you
3. Counting shares on Slush side fail
EDIT: but there agen I also noticed that I'm getting paid less for long blocks. It was usuly other way around since pool hoppers take part of the earnings... So Slush might take a look at the system....
Yes, it seems to be some problem at your side, because for the same blocks i have ~300 shares and 0.00032 reward on average with just 150MH/s