Sorry I have no real advice. I haven't worn braids in 20 plus years. I wore weave one time and took it out in three days because of the itchies and said never again.
I've been looking for youtube videos on how people care for and cleanse their hair and scalp under sewins because I'm curious. Recently, a stylist told me depending on whether you get a weave cap or not largely decides how to care for it. She said without the cap you can cleanse yourself but if you get the cap you need a pro to clean you hair. For the braids, I see no reason you couldn't lightly spritz the roots maybe every other day. I don't think two weeks would make it super frizy especially if you used a good holding gel to put them in. But again, I'm no expert.
"More people would learn from their mistakes if they weren't so busy denying them." - Harold J. Smith.