Is my engine f***ed?

2006 318Ci with c. 140,000 miles on the clock. I only bought it two weeks ago for a very low price so naturally no warranty or anything like that, but no noticeable oil leaks from inspection when I bought it.

Last week I noticed the car had started leaking oil onto my parking space and the orange oil light started to come on intermittently, but dipstick told me the oil levels were fine. So I gathered the orange oil light was to signify something to do with the leak, or a dodgy sensor, that I could fix in due course.

Last night on the way home from work suddenly the car started making very worrying noises (sort of a scraping/gravelly type noise) between 1,500 and 2,500 rpm, but would stop when revving any higher. Then the red oil light suddenly came on. I pulled over and there seemed to be a thin layer of oil on top of the engine cover, the dipstick was bone dry (after being at the correct level until only a few days ago) and had a bit of yellow gunk at the end of it (but not under the oil cap or anywhere else). I had a bottle of oil with me so I topped it up and all seemed fine, but I noticed within minutes that it was leaking oil again, from what looks like the sump - see photo below (taken from the front of the car just a few minutes after topping up the oil).

Attachment 8084

The car seemed OK so I drove it home. But this morning the oil was completely gone again and there was a very big pool of oil underneath it now. I got breakdown assistance to pick it up and bring it to a garage. Pending their prognosis... should I be worried? Does this sound like just a matter of fixing the leak, or engine damage?