I don't know what fault is showing up yet as the mechanic I go to is closed till tuesday so have to wait until then to get the proper diagnosis on it.
Certainly looks like limp mode.
There will be codes stored if the MIL light has come on, it seems the fault is either causing the MIL on shut off or start up, so certainly worth getting it scanned or investing in a code scanner.
Is the MIL light illuminated straight from start up or does it come on say 30 seconds afterwards or when you start to drive off or anything unusual like "running on" happen when switching off?
Any other issues like difficulties starting, uneven idle?
Was it a Honda dealership that did the glow plugs and fuel filter and do you know whether all codes were cleared when this work was done ?
Was there a specific reason for replacing the glow plugs and relay or was it just an attempt at resolving the issue. Also is it guaranteed to extinguish the MIL Light and run normally after stopping and restarting after 10 minutes
One thing to try today as obviously you cannot get the car in until Tuesday at the earliest is to bleed the fuel system by priming the priming bulb.
(I'm only suggesting this as you have recently had a fuel filter changed and it could be that the system still has a little bit of air in it and possibly causing a low fuel rail pressure fault, which is then cleared when you restart after driving a little while)
To do this:
1) Looking into the engine bay and standing central you should see the air filter box on your right, now head to the back of the engine and up to the bulkhead, you should see in a bracket a black rubber bulb that you can squeeze. (the location is shown in your handbook that you should have got with the car)
2) You can either undo the front part of the bracket to get better access to the priming bulb (preferred), or you can just keep pumping it until it goes solid, whilst you are there, follow the tube to the right and you should see the fuel filter, just double check that no fuel or bubbles are coming out of the connection to the filter (also just check that the filter looks nice and new!)
3) Once the priming bulb is hard, start the engine and accelerate it to around 2k and hold for 30 seconds, then let idle then repeat acceleration and hold for two more times. Check the car idles fine and then switch off.
4) Restart engine, is the MIL light on ? if so go for a small drive and come back, switch off engine and then restart, the MIL should have now gone off as previous. Leave the car to cool etc and try again later, to see if the MIL light comes back on.
Otherwise think it is best waiting for the code as it could be a number of things, which will be narrowed down significantly with the fault code that is causing the MIL to come on.