At your weight 5 lbs would be noticeable in how your clothing fit if it was fat (or water). If you're new to eating adequate protein and new to working out then it's possible you did replace some fat with muscle. Coming from a low fat / calorie and protein restricted diet our bodies have some 'repair' and 'making up' to do - once you start eating to build muscle then even something like walking can help this happen.

How long would it take for this new muscle to start working for you ? I'd expect to see some results by around 8 - 10 weeks. Of course, it could be water (I imagine its pretty hot in Memphis) from the heat and humidity, it could be water from an impending whoosh - but I'd bet some of it is muscle.

Nat