What does it mean if I have behavioral problem?

General term. 'behavior' is basically what people do; behavioral problems would be things people do that cause problems. The term is general, not just medical-- examples might be getting into fights, arguing, breaking rules, yelling back at parents, doing drugs, driving recklessly... And actions at odds with rules of normal society. Behav probs might suggest psych problems- depression, anxiety, add, etc.