Yep, an LC can definitely help with the medical side of things also. ALmost everything at this age is related to feeding, so LCs can do thrush, weight, unsettledness, sleeping.... ABA can also offer advice on all those things too.

Weight gains should alwasy be considered averaged over a month or so - they will vary a great deal from week to week. 140g in 10 days in not too bad, really, so don't stress out just yet

The sudden increase in feeding and unsettledness is very common, you'll find it happens every now and then.

Hang in there