Watch the Level 2: Blues Bends online guitar lesson by Jeff McErlain from Take 5: Blues Bends
One thing about a blues this slow is that it's really easy to rush, so be aware of that when working through it.
It's important to record yourself as well and listen back to the bends and phrasing. As any guitar player can tell you, what you thought you played isn't always what you actually played! It's an interesting phenomena and can be very frustrating. You think, "Man that sounded good!" Then on the listen back, "What the heck was I thinking? That sounded terrible!" It's a burden we all bear! Anyway, record yourself and listen back critically, don't beat yourself up about it (which is often very difficult to do). Just try it again and focus in little improvements.