I expect that the following is not uncommon, but I'd be eager to hear from some of you. I've been playing the same fretted 5 for almost a decade now, and decided recently that I really wanted a Carvin AC40 fretless for jazz gigs. Playing my new bass, however, has led first to pain in my fretting pinky, but has radiated into my hand. A friend who plays banjo, dobro, and guitar pointed out that she has had similar problems when getting on a new instrument. So, the two basses clearly have many differences - one is a 4, the other is a five; one has frets, one does not ... Is this normal? Am I just exercising new muscles? Will this go away with time (say yes)?