250kh/s is really low nowadays, difficulty wise it should be of an almost dead coin.
Mine on a pool, do you have any concern?
I was wondering since I decided to try solo mining a coin with 25 MH/s net hash rate and I appeared to be doing better than in a pool.
Leave it for a day and see how many coins you get and compare it with the pool. It's all about luck, you might find many blocks in an hour and nothing for a few hours and this is where the pool helps to normalize payments