Thank you so much for all your comments. Actually, right after posting this I was riding on the bike and saw another biker in front of me. He switched to the straight lane, as many have commented here. So I think that works for me, at least on this case. Lately I pay more attention to other bikers, not only while being on the bicycle myself, but also while driving, so I see what the do on stop signs, turning lanes, etc. One thing I've noticed, however, is that I never see them doing any kind of hand signs when turning or switching lanes. Seems most of them just slow down or wait for no cars coming at all, then switch lanes or turn, but without hand signs. I wonder if it is just a Dallas, TX thing.