There are so many points at which a western blot can fail. Did you evaluate your transfer with Poceau S? Do you have any loading controls? (other protein lysates to add to other lanes from known good samples). Antibody specificity, secondary specificity, and the readout. ChemE, HRP, etc. The more info you can help to provide the more troubleshooting we can offer.

Best of luck.

I agree with Craig Silver for the first problems.

For the second problem:

Maybe your protein was degraded by Protease. If you working with protein, you need to add Protease inhibitor in your extraction buffer. Always use ice bath when you working with enzymes or proteins and store your extract on -20 degrees

I would agree with previous answers, make sure you include in your lysis buffer protease inhibitors (Roche offers complete tablets ready to use). Besides, make sure your proteins are well solubilized and that the pH of your solution does not make them precipitate when you heat them before loading on your polyacrylamide gel. In such case they would be stuck in your wells. One good way to check is either to color your gels with Coomassie blue or to color your transfer membranes with red ponceau to be sure your proteins actually migrated and were transfered onto your membrane. After checking these points, you might want to make sure the primary and the secondary antibodies you use are specific and diluted to the right range. Unless there is protein degradation, i am pretty sure your isolation protocol is good enough. Just add the protease inhibitors and stay on ice.