Jude hated his pram/pushchair from 6 weeks till he was just over 1. It was a nightmare and i had to carry him everywhere but as he got heavier this got harder and harder!! I eventually invested in an ergo baby carrier which is great and quick to put on. Soon after he took to his pushchair at last!!
I used to just try everything i could think of to encourage him to like his pushchair. Numerous snacks, toys and when all they had run out and his started up i would carry him in the carrier.
As everyone else has said i have learnt not to panic too much as everything is just a phase that eventually passes!! Usually to turn into another phase.
Good luck, i can recommend an ergo carrier. I wish i had got it sooner.