You started off wanting to lose 75 pounds. Usually you lose around 10% of what you need to lose in induction and then 5% a month after that. So, I would guess that about 2 pounds a week would be a little more reasonable than 4. You have to remember that the closer you get to your goal weight, the slower it comes off.

Also, muscle building will cause your scale to either go up temporarily or stay at a weight longer-BUT you will lose inches. Please measure some places as well as weigh. I either lost weight OR inches, but not usually both at the same time.