Most customers report adjusting to the Smart Nora within 7 days of using it. You should sleep with it for an entire week (or more) before deciding how well it works for you.
Also, there are a few options to help keep the Smart Nora from waking you up: set the Smart Nora to have a delayed start, decrease the sensitivity of the Pebble, and decrease the pump strength. If you set the Smart Nora to have a delayed start, it won’t go off within the first 30 minutes of use. People are often easier to awaken during this time.