Nothing wrong with platform pedals

Shoe fit is very important, make certain your toes aren't touching the end of your shoes. I am loosing a toenail because of this from my winter shoes. Your feet do swell on the bike, so make certain they aren't TOO tight, and I have found this is more of a problem for me than shoe length.

While it is good to practice clipping in/out on the trainer, it is a very different dynamic on the bike as the trainer can't fall over On my first attempt to move to clipless I had used them in spinning class for about 6 months, but as I had only been riding outside for about 3 months at the time my body wasn't yet ready to add anything to the equation and I failed at that first attempt.

All of that being said, I concur with the advice to head back to platforms or BMX pedals until you are more comfortable - and you don't have to do that then. You can ride a gazillion miles on good BMX or platform pedals - nothing says you HAVE to ride clipless