My 8 year old son also has a high level of anxiety and gets frightened rather easily.  He has a quick temper and gets frustrated faster than you can say "time out".  It’s like he is on an emotional roller coaster.  Right after he has said something or done something out of anger, he becomes extremely remorseful and calls himself a "jerk".

On the flip side though, he is also VERY loving and emotional.  We enjoy long talks about anything and everything.

We have learned to take the good with the bad and work together on behavior modification.