When I attempt to add a second segment to a Bezier curve, it creates it very small and folded back on itself, almost like a circle. I create it by selecting the end point of the first curve and then Ctrl + LMB. I've tried this is 2.77 and 2.78c and get the same results so it's obviously something I'm doing wrong. Trying to find the new end point is difficult and when I do hit on it and drag it away, it generally wanders off the flat plane. Thanks.
I was finally successful in adding a second bezier curve, but not the way described in a Blender course I'm taking. If I do it the instructor's way, I get a curve folded back on itself with very little chance of straightening it out.
I'm using Blender v2.78c but I tried it on 2.77 and got the same results.
Here is how I have found I can do it.
At the end of the first bezier curve align the control handle so that one end points generally in the direction that you want to add the next curve. Select (RMD) the END of the control handle which points in that direction (NOT the end point of the curve), hold down CTRL and left click (LMB). The new curve will be added.