Maybe can try to change position...try leaning back so he is lying on your belly..that might help with the forceful letdown.
When baby gets bigger, you won't need the pillow anymore. Baby also has to learn to latch.
As for baby regurgitating feeds...it's pretty common. Just arm yourself with lots of towels or a burp cloth. It should be easier to go out if you are nursing as there are no bottles/hot water/powder to pack.