First Batch Taste Test

Firstly, I know that I definitely jumped the gun a bit on this one, I was just so damn anxious I had to give it a try!

So, I brewed up a batch of Brewers Best Pale Ale.
Boiled 3 weeks ago
Two weeks in fermentation.
Gravity readings were steady at 1.014 for about 3 days straight, so I bottled it last Sunday.
Decided to open 1 bottle yesterday for a taste test.

Poured really clear, no debris... very nice color, thick foamy head.

I could tell the taste was there, and it was good, but it was bitter. And not in a good, hoppy kind of bitter. Just... bitter.

I guess I'm wondering now if another week or two in the bottle might cure this? How much and in what way does the taste change while the beer is aging in the bottle?

I was reading some other threads that are similar to mine, and I know that I'm going to hear "wait" and "give it time", so I know that is what I have to do... I guess I'm just wondering how flavor is affected the longer it sits in the bottle?

Does it lose bitterness? does a longer wait in the bottle increase ABV? what actually happens, specifically?

The flavor will mellow. The carbination has a lot to do with flavor also. All of the extract kits I have done didnt tast there best until about 6 weeks in the bottle. They were good at 3-4 weeks in the bottle, but really hit there stride at about 6.