First, don’t panic :)
Second, dfhack keeps a few log files in DF’s folder (stderr.log and
stdout.log). Looking at these might help you solve the problem.
If it doesn’t, you can ask for help in the forum thread or on IRC.
If you found a bug, you can report it in the Bay12 DFHack thread, the issues tracker on Github, or visit the #dfhack IRC channel on freenode.