Nah, just one red bar only means a couple -rep's.
I do have to agree that it may have a little bit to do with your sig.
I have seen you reply in a manner that might make some of the younger people around here give you a "-" though.
I always try and word my posts towards younger people (although, the last couple days I have posted more towards "my true self").
It's a matter of perspective I think.
I will not give someone -rep unless they really deserve it. I am more apt to give +rep "on principal" (the particular post the person makes may not really deserve it, but the person making the post does because of the effort he has put into this site).
I would much rather go to my grave not needing my gun, than go there wishing I had it.