Quick question

I bottled a California Imperial, by Brewers Best, about 2 weeks ago and I tried one yesterday. It was pretty "thick"... It didn't taste bad like it was infected or anything, but the flavors were pretty pronounced, more than it should. It is recommended that it age for 2 more weeks, so I'm thinking that it will mellow out a bit. The only thing that I did different was that I kept it in the secondary for like 3 weeks (too busy to bottle). Should I be worried?

No you should not worry. Give it more time and let it age a bit. Seeing as it is an imperial type beer, you need to give it way more time. This beer might take a few months to come into it's own and be the beer you are looking for.