frequent bloating, rumbling, gas at night, constipation

I am a 23 year old male who has been experiencing some problems over the last little while with my digestive system,

going back to about june i had been experiencing infrequent bloody stools, most of the time there wasnt any, but when it would happen there would be quite a bit in the bowl. I didn't think anything of it because it never happened for a while but around the end of october I experienced a really bad bout of constipation and bloating. Since then i experience really strong wind late at night when i'm in bed, sometimes its so loud it wakes me up, this is coupled with the feeling of gas moving through my system before falling asleep. I have a bowel movement every morning like clockwork, and havent seen any blood recently. i also notice that when i bend over slightly i can feel light pressure slightly above my pelvis on my left side, which is also the same spot that i can usually feel the strong gas backing up.

I've been to the doctor twice regarding it, both times they have said its symptoms of IBS, and that there is nothing much i can do, other than using laxatives when i'm constipated or using immodium to relieve strong bowel movements.

are the symptoms i'm speaking of typical of IBS ? or should i ask a referral to a specialist ?