Brown discharge is old blood, i would not worry about it if you have no cramping and you are not bleeding red blood sometimes you will spot pink . Spotting in the first trimester is common, if you have cramps or start filling a pad every hour then worry.
Well girl my only advice is what my doctor told me to do, lay down, put yourself on bed rest, drink as much water as you car, and put a BUNCH of pillows under your legs to elevate them super high. If it doesn't stop go to the ER. I would still try to call your dr most have after hour numbers.
Could be implantation bleeding but I would call the after hours dr and ask I'm not a doctor so I don't want to give you the wrong info. Hope it gets better!💛