Audi Repair Questions? Ask a Mechanic for Answers ASAP
Check to make sure your oil cap and your oil dipstick are fully seated- if not they can throw a leak fault.
If the CEL is flashing, then that means you have misfires occurring, which is bad. But just being on is not necessarily going to cause a problem.
If necessary, many of the large chain parts stores like Autozone will read faults for FREE (and may clear them if you hint that you would like that to happen, or tell them you'd like to clear them and see if they come back before buying any parts.
if there are any questions about faults if you have them read, post them up in this question thread and we can figure out what is causing the CEL
Unfortunately, with VW and Audi, the faults don't clear on their own when you fix the issue- you have to clear the faults with a scan tool, and if they are still present on a test they will fail and set the light off again.