Bike gear help

I wasn't able to move my bike up the gears, on both the front & back. A lot of force was needed. I thought it could be due to cable friction, so I removed cable from the pitch bolt, to feel how it pulls through the housing.
However I now can't move up the gears at all! I've tried adjusting the tension with the barrel screw. However now the derailleur wont go higher than the smallest sprocket.
I'm know i'm probably being stupid.. but any advice?