Help! My baby isn't sleeping well...

We are having such a difficult time with trying to get him to sleep longer. My 11 week old boy isn't going longer then 3 hours between feedings and he used to go 4 when we were able to swaddle him but recently had to stop because he started rolling over. Currently he is in a pack n' play next to our bed on my husband's side and we've tried everything we can think of... we have dream fed him, he is in a sleep sack, it's dark, the noise maker is on, we do our bedtime routine, etc. We are really wanting him to go 5-6 hours but would be happy with 4 because between feedings he startles himself awake like every hour.

We also would like him to wake up consistently at 8 but no matter what we do he always wakes up at 6.

Any advice or tips, I go back to work next week and would like to be functional.