So i've been on the pill for 4 years and i skip my period for three months. it's usually perfectly fine but right now i have a week left until my period and im bleeding? not like spotting like actually bleeding and im so confused is this just breakthrough bleeding?

Yes, irregular bleeding is a normal side effect of the pill, at ANY time while on the pill.

Skipping breaks can cause you to bleed at other times. It’s not a guarantee you won’t bleed at all if you continue to take pills