I had a sleeve not a bypass and the 1st 2 weeks was purely clear liquid so please check with your provider about crackers, I know I couldn't.
It took a good few weeks to get the wind under control and get it moving properly so that I wasn't uncomfortable, keep moving round and drink peppermint tea that realy helped me move mine in the early days, you should find that each day does feel a bit better than the last one.