Does anyone know if its possible to get out of a Penguin window contract?

We had some pushy sales people at our house for 3 hours on Saturday and after their convincing demonstration, we signed a contract, we then signed something that said we have 3 days to change our mind, but only under strenous cirstances. After googling the company and see all the complaints we want to change our mind!!! Can they penalize us for that??