my sister has invisialign and had some gum bleeding the first few days as the retainer didi not fit exactly perfect over the lower teeth and scraped on the lower gums in the front teeth right where the teeth met the gums..
few days later, the gums kind of got better and the retainers started fitting better as the teeth shifted.
Good Luck!
Braced Twice. Wear Your Retainers!
Ceramic Braces On Top and Metal Braces On Bottom, Palatal Expander - First Time Around
Metal braces top and bottom - Second Time
Now Wearing Retainers At Night!