Now that my first tasting when ok...

I have a question about head retention. I noticed that my beer, a brown ale, has carbed up after about 9 days in the bottle it had some good head on it but quickly fizzled out. what is this a sign of? Still green beer, not enough co2, I didn't pour it correctly, other?

I am very happy with my first attempt as the beer tastes fine, although it does need to mellow a bit, I am just trying to learn as much as a can at this point.

Thanks,
Chris

9 days isn't that much time. Leave it another 9 and it should be fully carbed and not as green. Don't hesitate to taste it along the way to see what it's like as it carbs and conditions, but don't rush to start drinking it.
Start another batch to make the waiting easier.

Congrats on your first batch.

Head retention is not just based on the beer. If your glass has soap residue or are washed with jet dry, head retention will be lost.