Mb2007bluetec

I have a 2007 E320 bluetec. Il'' give the problem first then what i've tried.
I just left my house and got around the corner, then all of a sudden it didn't want to go above 7 mph. Then it stalled before I got it home. Came home from work and it started. I drove around block, still won't go above 7mph. Happened in the winter, so i thought maybe fuel filter clogged, so i changed it. Car still doing same thing.
Now it starts and runs for only a few seconds. It will continually do this. Start and run for just a few seconds.
Pulled seat cushion in back. Pump is coming on. Stays on until car shuts off. This is pump on passenger side.
I've heard people say this car has a transfer pump that may be causing this problem! Is this true? Could i have a weak fuel pump?
Car was running perfect before this happened.
I bought a scanner and these are the codes I got:
P0088 high fuel pressure
P0087 low fuel pressure
P0123 has something to do with throttle
Car has 150.000 miles
I bought with 75,000, so my guess is none of this stuff has been changed. Everything has the OEM hose clamps.
These are numbers off of driver side sending unit: Bosch 211-470-16-41 (1-582-881-000)
thanks:
update
Pulled lines off sending unit on drivers side and fuel can out with pretty good pressure.
Can someone explain how the fuel is delivered through this system?
I see the pump on passenger side and sending unit on drivers side. Does the fuel get pumped from the drivers side to the passenger side sending unit, and then to the engine bay? On the sending unit there is two lines coming off it. The line toward the rear is the one fuel came out of. So it's supposed to come from the passenger side pump to the inlet on the driver's side sending unit, then out the other line to the engine bay.
And if the flow is good here, then I'm guessing it isn't the fuel pump and possibly something else causing this problem.