A gallon of water weighs 8.4lbs.
An 8oz glass of water is about ½ pound.
It’s entirely conceivable to put on 3lbs of water weight.
Maybe don’t weigh daily if the fluctuations are driving you batty.
Heck, as a woman, I can put on 6-8 pounds in a day or two when my cycle is nearing. It’s interesting but not worth the angst to worry about it during that time.
I’ve long since come to terms with the fact that my healthy weight is not a single number, it’s a range of 5-8lbs. As long as I’m in that range, I’m fine.
This sounds reasonable…especially if upping the workout regiment.
Muscle microtears retain water and are 100% normal. A few weeks of working out and this will all level out and start declining again.