Metformin side effects & weight loss. *TMI*

What side effects did you have on Metformin? How much weight did you lose the first month? I've been on it 5 days and lost 2 lbs already but I've been making nonstop trips to the bathroom. Due to this I'm always thirsty! Just wondering if these nonstop trips to the bathroom are temporary while my body is getting adjusted to the meds or if it will be a chronic problem??? I'm also getting stomach aches on occasion even though I don't take the meds on an empty stomach. Thanks for your input!