Odds for that results are impossible. . . why are this sites always cheating?
Firstly, wrong section. Secondly, 13 losses in a row with around 49 chance of winning each round is not impossible at all (people have gotten as high as 18 losses in a row, some claims even more). If you only lost few satoshi then consider yourself lucky.
0.51 to the power of 13 is 0.00015791096563, so the chance of losing 13 times in a row is 0.015%. Unlikely, but not possible. Also, you probably wouldn't even bat an eye if you won 13 times in a row, which can also happen, but with the strategy your using, it won't benefit. If you still think they cheat, bet LO instead. Those 13 losses are now wins.