[ Other - Society & Culture ] Open Question : Handling a situation where pride and dignity is on line?

I don't know how to title this so i did what i can. here is my problem, i been working at a office where my colleagues (one of them) is very cheap, eventually he got opened up and when other guys joined in office.he started to make impression that he is senior (which he is not, atleast of me) and that he told me number of things. now having said that the other guys started following his lead until one guy pointed out to me my work. which everyone admire (but they don't) and we had fight and i told my reporting officer and he sat down and talk. as i was pissed off what happened the prior week and i been working my as* off fixing the guy work (who initially gave the impression he is senior) as he screwed up big time while making my work double. and one day we had quarrel as he said u disturbed my work and i told him. what should i be doing fixing your problem which u give me or work my own work. and we heated up etc. now its been 2 weeks since we aren't talking. he know he passed the border line, As for me i don't have that thing in my personality which "make other people fear me or think that if they think stupid he will kick our as*." he is quite but there is one guy who is 2 months new and he do same, tease me, mock me on my work (he do it to fool around) but i don't like it all. now given the above situation i wanna know two things. 1. How to deal with people like my colleague which is quite with me, coz he know he passed the border line and yet he admit his mistake and respect my work qualities. 2. As discussed i lack the domination/ the power of making people feel that they don't say anything work to me or else. the scary dominating kind of guy. 3. else whatever u can advice me pls do