After driving and parking the truck it will not start?

Upon first turning the key forward, started or not, the lamp out light flashes 30 times and stays on, the check engine light will flash 10 times and go out, the lightning bolt will flash once and go out. When started just before takeoff or at slow down when RPMs reach 500, truck begins to slightly shudder. While driving at 50 MPH and 1,500 RPMs with overdrive engaged, the truck shudders. At 2,100 RPMs, the truck shudders. If you shut overdrive off it seems to get rid of the shudder most of the time, although sometimes it doesn't. At each of these times the check engine light will also come on and flash until you get to a speed where it is no longer shuddering.
I currently do not have a muffler, nothing past my cats. This week I've cleaned the throttle body, replaced the EGR, PCV valve, spark plugs, wires, and o2 sensors. I currently have no codes. I should mention that once I changed the o2 sensors and took it for a test drive and noted the shuddering I mentioned earlier, I took it home, parked it. And now it will not start at all. Not a click sound, or anything.
Any thoughts on what might be causing either issue? I plan to get the muffler and tailpipe pipe later but wanted to address some other issues first. I'm thinking I may need to change my coils, possibly clean the MAF sensor, but I'm truly hoping it's not my PCM/ECM.