Turn signals on the side of the fenders not working

The sidemarker lights come on steady when you turn on the parking lamps, and they stay on steady when you turn on the headlamps. You can (and should, if you're in there working on the wires) make a simple mod to the front sidemarker light wiring so they burn steadily as sidemarkers and flash with the turn signals; see here.
This is a very good safety improvement, as your turn signals become visible to
the side instead of just front- or rear-on. Do it only to the fronts, though, not to the rears.

You say your sidemarkers don't light up at all. Are your parking and tail lamps working? Because the sidemarkers are fed off the same circuits (front sidemarkers + parkers, rear sidemarkers + tails). If the parkers and tails are working, then have you checked to make sure your dead sidemarkers aren't just because of burned-out bulbs?

Extra-fast flashing of the turn signals means you've got a burned-out turn signal bulb OR an improper park/turn or brake/tail bulb OR a ground fault at one or more park/turn or brake/tail sockets OR a faulty flasher.