Everything you've described sounds pretty normal to me, hun Getting the hang of BFing is definitely a learned art for both you and bub, most people I know have said it definitely didn't come naturally!
I agree, expressing for comfort is a good idea, your breasts are probably nice and engorged as your milk supply really hits its stride - it's nothing to worry about, little Elliott will soon work out proper attachment and how to cope with getting a big spray hitting his neck
ETA Trill posted at the same time as me lol - yes, lying down to feed, or feeding with you laying down and him across your chest is a GREAT way to help with a big letdown, Hayley and I were always lolling around on the couch or in bed instead of sitting up

I know it's sooo hard right now to persevere with BFing issues while you're healing from delivery, coping with the hormone fallout and the adjustment to being a mummy in general, but it really does sound like you're doing a fantastic job, sweetie! Just keep going with what you're doing, it sounds like he's getting plenty of yummy milk and that your boobs are working just fine. The engorgement issue will sort itself out, hopefully within a few days although it could take a couple of weeks before it settles (I was sooo engorged for sooo long with Squirtle lol, but she was one of those babies who'd just open her throat and LOVED getting a huge letdown, a lot of babies splutter and get upset), and it sounds like you're doing a great job trying to teach him how to attach properly.

Chin up babe, keep on truckin', BFing is rarely easy or natural to start off with, but it sounds to me like you have all the right tools and the right attitude to get you into the swing of things in no time! I promise it'll get easier and better Good luck!