Sounds like someone needs there ego stroked, and went fishing for a compliment

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Seeing as there is no real question here, I can't see any other use for this post. Of course 23 lbs in 3 weeks SOUNDS good, but there is NO WAY you could've added more than 5, maybe 10 lbs of lean muscle, and even that would be absolutely amazing!
No one can really make an accurate assesment of your gains, from excellent to bad or whatever, since you didn't include a before and after picture. It's a common rookie mistake to use the scale as your main indicator of progress. If it goes up, I'm doing good - and if it goes down, I'm doing bad. I have to admit I've fallen into this trap in my early days of lifting, and all it did was leave me with a lot of fat that had to be dieted off.
So unless your a linebacker or something that will benefit from sheer mass (whatever it consists of), I suggest that you put away the scale(mentally) and focus on the mirror and body composition readings.