Wow, good for you for getting approval on a 2 level ProDisc! Where did you get your superpowers!?
The wide range on hospital stays is appr. 2-7 days, with most being 3-4 days. So your expectation of 3-4 days seems rational. Since you’ve been reading the site, you may already know about some of the post-op resources here:
http://www.adrsupport.org/post_op.html
The paper I wrote on recovery is based on my own research and experiences. It’s a bit crusty, but you may get a few things out of it to help you through your recovery (e.g., deep breathing).
If you are the type A type, don’t worry too much – you’ll be pretty tired from the major trauma to your body! In the first few weeks, it’s important to walk a little bit; just being vertical helps all of your body systems.
Where you must be careful is in the second, third and fourth months of recovery. This is where you may need to moderate your activities, especially while the implant is “osteo-integrating” into your vertebrae. That means no skydiving, jack hammering, heavy construction, water skiing!
Everyone’s mobility after surgery is a bit different, but you may expect to stumble around awkwardly for 1-2 weeks. Being a 2 level, maybe 2-3. Again, recovery times vary because of many variables: your spine condition, your overall health, the number of levels retracted/implanted, surgery time, etc.
Hope this helps, good luck with all!