To clear things up you have three lights that can come up for failures
1) check engine light (looks like block with a lightning bolt)
2) glow plug light (coil and it flashes)
3) DPF light
A check engine light is a more general light, it could mean you have issues with any part of the system mechanical, electrical, or computer related
A glow plug light error usually comes up with an check engine light, this is related to fuel, or glow plug issues.
A DPF light comes on with anything emissions related for DPF, or pressure related.
Some common issues I have seen and had customers with on DPFs:
1) clogged DPF pipes (VW has had four revisions of these downpipes since they first came out)
2) Bad sensors or bad gaskets
3) Intercooler pipes poping out plugging DPF
4) Turbo chargers going due to plugged or caked DPF units
5) flapper valves clogging and not operating properly so when car regenerates the particulate into ash you get a less eff. burn
The OP has an unknown issue period, I do not know if it is DPF related. Lets see what the codes/ dealer says
Got Haggis- I think your car was going through a regen cycle which goes into more detail on myturbodiesel.
11 golf- Lets wait and see what the codes where, did you have any other strange feelings or problems? Could be a loose plug, bolt, nut, or connection....