You hit it right on the nose!
That is why I had such bad pain last week....it's usually just a dull roar that never goes away and then it hits....BAM!..(sorry Emeril)....and of late, each BAM has been getting a little worse than the last BAM. It had been pretty consistent up until recently and now it is escalating. The last bad BAM also brought some weird numbness with it too. My butt went numb...a nice little circle of about 6inches all around my anus. Didn't have any bowel or bladder problems but I was as numb as could be. It's when weird stuff like that starts to happen along with the BAMS, that gets me! I talked to my neruosurgeon's office today and let them know. He just got back from Portugal today.
So you've pinpointed the symptoms perfectly and now watch for the extra symptoms that can go with the BAMS! Signs of worsening.
Hope you feel better soon and the dull is duller and the BAMS are smaller.