A streak of 13 losses is very common on a 2*payout.
Take a coin and flip it about 10k times, the possibility of you flipping head (or tail) 13 times (or even more often) in row while doing this is very high.
you have honestly flipped a coin ten thousand times? suuuure
No I haven't
But this shows that the possibility is quite high even on a normal event like a coinflip if you do it 10k times.
And 10k bets on primedice is almost nothing for most of the users.