Why do guys do that hinting kind of cough when there in a room with other guys and how many times they cough?

and also what does it mean about how many coughs or eh'hms like catching their coughs or of the such, does it mean that they are saying that they are the toughest person in the room because i have it happen at school all the time but i train in muay thai, bjj, kickboxing, and western stly boxing, and i dont do that, im not looking for anyones approval but i just laugh in my head at them because they know nothing of anyone in that room but im not the type of person to go starting fights with random people but i sure as hell will end one, its just i pity them, for them to try so hard because ive seen little skinny guys that the only thing they have is there height but it so funny, i just want to understand why people do it. and that does the certain shortness of ones hair like a 1 which is really short and 2, 3, etc. mean thats all they care about. like 1 as there selves or there money or if its a 2 length then there money and there girlfriend and what would the other lengths be such as a 3,4,5,6,7 etc. or is it just 1 and 2 hair lengths really matter/count. and to the gangsters of thugs that think that scratching there backs mean that they have a knife or anyone else who portrays that, is that i dont need any weapon to hurt people just my two hands, nuff said. im not a confrontational person so just be more humble then provkiong ok, mercy goes along way with god, seeing how that god shows us mercy everyday for the sins that we commit eveyday and how that sin fo the body is so much more worse than sin of the world. sothanks to all who answers in advance.