I definitely recommend a thermos of hot chamomile to sip while feeding (as long as you like chamomile!) As far as I know it's fine while bfing. I often have a hot milk if I've been awake for a while and need to bring on the sleepiness. Also, perhaps some yoga breathing exercises (I mentally give myself the instructions in my yoga teacher's voice), or a cotton ball soaked with lavender oil, which you lift to your nose and have a little inhale of every few minutes. When DS was up for long frequent feeds in the night I found that it was harder to get back to sleep if I used my phone to entertain myself, be it reading an ebook, fb or games, and I know you said you don't use those, but conversely, I find even now that rather than lying there awake and frustrated, I'm better off turning on the bedside light and reading for a bit. I'll often start to get drowsy, and that's the moment to turn off the light and close my eyes. I think it's something to do with the story in the book occupying my brain and stopping all those thoughts which otherwise might keep me awake.