Secondary profession

Im in the process of chossing a secondary profession but have come across a poblem. Im guessing the idea is that you talk to all the Profession leaders, try each one out and then finally choose one. I'm in the process of trying a second secondary profession out but have decided on the one I tried previous, if you get me. When I go back to Toga and he asks me what secondary profession I want I only get one choice and that is the last one I tried and none of the ones previous to that. When I go back to the Assasin's Guild Leader, which is the profession I want as a secondary, I no longer get asked if I want to try it out again. Im confused? Why can't I choose any profession as a secondary and why do I only get one to choose from?

I'm guessing...you accidentally took a quest reward or something from Togo, thus sealing your fate for a secondary profession. But don't worry, after 4 missions you can change your secondary profession again, so just live with it for a bit.

If that isn't the case then perhaps this helps:

http://gw.gamewikis.org/wiki/Getting...Skill_Qu ests

Thanks, both of you.
I think your've both pretty much answered it. I think I went one quest too far with it!