I've played 365 games...and have 6 credits.

Why? I bought Party4U - HolyNight Remix V2 (500 creds, difficulty 9 but seemingly much harder), Stay With Me V2 (250 creds, difficulty 7), and just a few minutes ago I bought NeoMax (500 creds, difficulty 10 but seemingly easier).
So okay...let's just say 131 credits. And maybe add on the few that I might've lost from past challenges.