@OP: The clock adds a competitive component to the game. Chess is about competition! If you believe you can win, even if it's on time, then you have every right to pursue it.
Your opponent has his own obligation to manage his time wisely.
Your opponent was incorrect that you "had" to resign. Attempting to pressure someone into resigning is unsportsmanlike.
However, one may use underhanded techniques to try to force wins on time, and of course these should not be used.
You were wrong to taunt your opponent. We all need to work together to keep this game and great website civil. However, you were definitely not wrong to pursue the victory in the manner you described.
I should add that of the three elements of Chess that you mentioned, "time" refers to the time element on the board itself, not the time on the clocks. In that context, "time" refers to tempi.
I was playing a 10 min live chess match last night and I was in bad shape. The only difference was I had more time than my opponent and he was struggling to beat the clock. My friend told me that chess is a sport of "time, space, and material" and he says it takes all three to win. After the match my opponent said in the chat box "you had to resign, I was winning" to which I replied, "I'll take a win any way I can get it" He then cursed me using clever abbreviations like fu and sob and I taunted him by calling him a slowpoke and offered a rematch. At this he replied he would never face me again. Did I do something wrong? Isn't winning winning? or did I disrespect some long standing tradition of courtesy by pushing for a win on time? Is there any shame in that? What would you do?
here's the game if you're interested, although I'll admit it's a pretty sloppy one.