The database is showing that you stopped mining at 2013-07-24 01:18:07 PM and then you started mining again at 2013-07-24 07:41:07 PM. Our last block was found at 2013-07-24 08:51:30 PM.
By you stopping you lost alot of shares in the "N" of PPLNS. Our "N" was set at 150k shares. So you saw less paid out.
Remember PPLNS rewards dedicated miners and wards off pool hoppers
On a side note: I will be raising the "N" of shares later today due to the much longer rounds were getting lately.