Thank you everyone!

It's much more clear to me now.
I've always followed local custom even in terms of crossing myself etc (hope that's okay), mostly because I don't really understand why people cross themselves differently. Is there any significance in this at all? (I mean crossing yourself right to left, or left to right)
I say the Filioque during Latin rite Mass, and don't say it when I go to Eastern Catholic Divine Liturgy... I don't mean to pray different things though. The history of the Filioque seems very complicated. Is it true that in Latin, it doesn't imply what it does in the Greek?