Blown Turbo??

Hi all, apologies if this has already been discussed
I have a 140 TDI sport with stage 1 remap, turbo has 'woooed' since the remap over 12 months ago but not loud and pulled like a mother so I didn't worry, on the way home from work giving it a few beans I had a complete loss of turbo power, checked the rear window immediately and no big puff of smoke, the car drove home on just the engine power, turbo spinning but with a very quiet and constant whine and no fault codes on the dash. Im thinking a blown Turbo?....I was under the impression that when a Turbo goes through either oil starvation or debris getting it it was catastrophic and can damage the engine?any ideas or experience of this happening? cars parked at home and I daren't start it back up incase of damage...
thanks in advance guys

cheers zedzo, after trawling the net since getting it home im hoping its a pipe as there wasn't any smoke or pop/bang and it was still spinning, albeit at one speed and with no beneficial effect to the engine all the way home, it stopped imediately as soon as I turned ignition off so hopefully thats a good sign, going to get a good look at it tomorrow but planning on needing a recon/upgrade all ready to compliment the chip, 'hope for the best-expect the worst' and all that, mechanic friend has offered to remove/refit so that should keep the cost down

just an update, started the car yesterday and white smoke started from the get go, turbo spooling up but sounds like its bearings are gravel so turned straight off and thats def a replacement needed, got a couple of numbers of mechanics friends contacts to ring tomorrow but if anyone knows of anywhere in tyne and wear that they have had experience of that would be much appreciated. cheers guys.