Service Engine Soon low oil

[phathom]

So I got the X5 at 121k miles one month ago. I did an oil change on it right away. I filled it up with Mobile 1 full synthetic to the middle of the fill indicator on the dip stick. New filter, crush ring, o-ring, etc.
Between driving in town and now a road trip I'm on, it now has about 124k.
It has driven great, but I just went to the store and on the way back to our in-laws, the service engine soon light came on. We don't have a lot of things to check on these without a code reader, but I did check the gas cap and the oil level. The oil is only up to the ball on the end of the dip stick, not the indicator bar itself. With that it looks like down 1 to maybe 2 quarts at most.

I'm obviously going to fill it up with more oil. I looked underneath and didn't see any signs of leaking. When I changed the oil, I degreased and detailed the skid plate so it's spotless. Other than some normal road grime, it looks the same. No oil marks. I don't think I'm leaking, but it's possible, maybe burning a bit. It's about 1.5qts over 3k miles so it's not a fast leak, it could just be consuming some.
Normally in my other cars using conventional oil I would have changed the oil again at 3k miles and normally would see about 1/2-1qt low by that point in all my cars, EXCEPT my E46 I had. That I would run around 10k and have zero consumption.

My question, would the low oil level cause a SES for just that, or possibly low oil pressure? Also is this level of consumption fairly normal for a M54? If not and it is a leak, what is the most likely culprit?

Edit:tried to search, but the search function is broken and throwing 404 errors at the time of posting this.