i always laugh at anything,,,,, i laugh at wrong moments?

[Badboy]

for example,
if someone is sad or angry,,,, i laugh
if someone going through hard time,, i laugh
sometimes it pisses many people
i tried to stop laughing by thinking negative thoughts,,, rarely when it works
sometimes i feel something wrong with my brain

is this bad?
is it a symptom of a bad thing?
what should i do?