A door that will not open is worth ten seconds of attention before a shoulder is applied. Swollen in the frame is a different problem from bolted from the other side, and only one of them yields to force.
The people who reliably get through things are not the ones who push hardest. They are the ones who have learned which kind of stuck they are looking at, usually by getting it wrong a few times first.
Pushing through remains the right instinct. Aiming it first is what makes it work.