Its gets better hun.
Im day 5 and it still feels tight when i sit up in the morning and move about.
After my first BA i was scared to take my bra off as it felt so weird but as they days go by its gets alot better.
Everyone heals at a different rate and if you have had unders they take a little longer.
By the time you go to see the nurse in a weeks time and she takes the strapping off im sure it will be fine.