Dark oil can be interpreted two ways. It means the engine had worked hard, but you should be glad to know that the oil is doing its function properly, i.e., absorbing all the contaminates and protecting your engine.

In my case, the oil remained mostly 'syrupy gold liquid' until it was near 10000km service mark. Oil consumption occurred during the time when it had lots of cold starts and peak hour driving. But I did not get the low oil pressure warning, probably because I checked the oil level regularly.

Same oil consumption thing also occurred to my other older car. I thought it was because that car was worn out...

I reckon you need to monitor it for a while (weekly dipstick check, under car check for leaks) and then decides what to do.