Cycle it is still very early days for your milk supply, it really is. Lots of skin to skin and feed, feed, feed. Even H suckling at the breast will help your supply - as will lots of feeding at night. Concentrate on sitting on the sofa and doing nothing but feeding - it will pay off. Some jaundiced babies will be sleepy so they don't feed as much, so you then get in a cycle of the jaundice getting worse and then they feed even less.
Also, step away from the scales, daily weighing is no longer recommended. Ask/tell your MW to look at other clinical signs of well being. Wet nappies, pooing, awake and sleepy times, cying for a feed. Not everyone feels a let down either, so don't use that as a sign of your supply. Keep the faith in you and H 
Pet - if F is a thrasher, swaddle him nice and tight before a feed and then he can't thrash, although that won't stop the woodpeckering! If you try and latch him on before he's gagging for a feed this may help with the bobbing head.
Also, try NOT to support the back of his neck. F needs to latch himself onto your nipple, not you putting him on there. A good analogy is someone else trying to give you a drink from an open cup, it's hard isn't it? It's easier for you to bring your mouth to the cup when someone else is holding it, not vice versa.
What you need to do is support him by his shoulder blades (his head won't fall off honest!) when he's laying lengthways across you. If you bring him towards you with his shoulder blades he is able to move his head, neck and mouth forward and latch himself on, then you can use a cushion to support your arm and his body weight.
Blimey this is hard to describe in writing, but the position you want to aim for is:
Take your right arm and bend it across your chest so your elbow is touching your right breast and your right hand is touching your left breast. Now imagine F laying along the length on your arm with his tummy to your tummy and his shoulder blades are supported by your splayed right hand (so you're feeding from the left breast). At first it feels very awkward, but lightly support his head or your left breast with your left hand and soon you'll both get the hang of it.
God that was an epic one wasn't it 