2006 BMW 330 power loss

Engine Mechanical problem
2006 BMW 330 Manual 24,000 miles

I have a bmw 330cd m sport, went out in it yesterday drove as I thought was fine until I put my foot down, but seemed to have no pick up/acceleration, had only traveled 10 miles so returned back home after checking oil and water, no warning lights came on dash. When idling sounds fine, rev it, fine, hold down accelerator until you get to 3,500 rpm then it seems to hold back, could you please help me with this problem if you can thanx steve