Week 2 and BM is stretching way more than the POTG. Could turn into a bit of a problem and I'm honestly not sure how to deal with it. Both are looking pretty healthy and seem to be developing well. More soon!
I'm kinda having same problem as you atm. What helped was getting a kitchen scale to weigh your medium bag dry then fully saturated and you deduce the water content for a small plant then you can do proper drybacks and maintenane shots as well as how much she transpires once they pick it up. Note that a standard 5Kg scale won't take more than a 2 gallon and you will probably have to make a stand to properly use the scale so check the scale capacity for your medium but if you can calculate water content you'll do better in a smaller bag.🙌