What Causes Gurgling And Rumbling Sound In Left Side Of Abdomen?

For about the last month or so Ive been experiencing lots of gurgling and rumbling on the left side colon, some feeling of cramps, but mostly the gurgling and rumbling. Passing some gas, though not as much as it seems should go with all the churning. Sometimes the "pressure" and crampiness is on the right, sometimes both, its really different all the time. Some days are pretty normal. Not much change in regularity, though seems like quicker transit time and looser stools and instread of one large movement in the morning, I have that one and sometimes a few smaller ones throughout the day. Stool shape is almost always different, sometimes fairly "normal" sometimes all sorts of shapes, and some have had obvious undigested food, sometimes from a few hours before.
The rumbling is pretty much constant lately and there is also alot of mucus, not white, just a sliminess when wiping. Some is mucus Im sure, but some may also be cause by the Citrucel since Im a regular user due to history of IBS. Noticed some mucus with several tiny specks of bright red blood.
Any thoughts? Cant get in to see gastro doc for a few weeks since they are booked, but Im pretty nervous. History wise I have family history of colon cancer, dad died of it at 68. I had one colonoscopy 2 years ago, 2 or 3 rectal polyps removed, due in another year for another one. Complete physical 6 months ago, all levels normal except low on vitamin D. Pretty worried here even though I know it wasnt that long since my colonoscopy.