this is my experience - my baby had the same problem from 6 weeks as well. we fed him the rid winds medicine, it helped alittle, but he was still very much in pain, cried for 4-5hours a day and refused to feed, breast and bottle.
the doc told us it's probably colic, and i had to watch what i eat. no dairy, soy, wheat, peanuts, spicy food. his advice was also to put the baby on his tummy after every feed for at least an hour. it helped alittle, at least that got baby to return back to feeds, but the crying for hours still went on. this continued till he was about 11 weeks or so.
i went back home and my parents taught me to fry onions in chinese rice wine, wrap it up in a towel, when it's cooler, rub the baby's tummy and back. the effect was immediate. he expelled all the gas thru farting (seriously, it was a series of non stop farting!!!). then they used some sort of chinese medicine called so hup, wrap it around his navel with a towel and let him sleep. this was the only thing that worked tremendously for us. now i do not have to use the onions or the so hup thing after 3 weeks of faithfully applying on him. he still cries from gas, but minimal like only 15mins.
im really not sure if it's my parents' method that worked, or that colic just left us after 3 months, he's now 13 weeks. but i do understand the pain, and all that crying he did, left me crying as well cos i felt helpless towards him and all i could do was to hold him tight.