Hi there. I HAD a very high need baby, she is now 7, and very delightful - intelligent, beautiful, witty, sensitive. However I remember her baby days with pain, she was very demanding from the word go, refused to breastfeed, cried a LOT, and used to make this wierd moaning noise when either over or under stimulated! Also needed a lot of attention.
I am sure your little lad will calm down eventually especially when he is old enough to learn to play by himself.
I do believe that sometimes boredom is good for kids - if you are always playing with them and always stimulating them they will never learn to be resourceful. I also think sometimes that over-stimulation i.e too many outings, visitors, toys etc can cause them to be fretful. So it's all about trying to get a balance that works for both of you.
How about providing him with a "treasure basket" of different objects such as scarves, spoons, blocks etc and then allow him to explore it for sensory stimulation - just put it down in front of him and let him explore, don't play "with" him. You can change the basket regularly for variety. Sometimes a nice bubble bath with some toys (him!) gives you the chance to sit close by and just have a few minutes peace. I must say too that I did use the "baby genius" videos and similar for some quiet time as well - DD loved them and they have nice soothing classical music in the background so quite relaxing.
I also found with my DD that I needed to do certain activities with her that I also enjoyed, just for my own sanity - I used to go to a lovely baby/toddler group, actually she pretty much hated it but it gave me the chance to have coffee and chill out with other mums.
I lived abroad when DD was born and had no family nearby. It was HARD. But it did get easier and honestly she is the loveliest child now. I think high needs often comes with high sensitivity and for DD this is true, she can be very emotional and needs lots of cuddles but also plays independently for hours and hours now - very little whinging involved!!
Good luck, remember your baby has needs but so do you. If you can get a babysitter or something occasionally I am sure that will help - I organised for someone to have DD once a week for a couple of hours so I could swim - bliss!