understanding redox reaction

I am a total noob in chemistry, so sorry in advance if this is a very stupid question... I am trying to solve this redox reaction:


$$\ce{KClO3 + FeSO4 + H2SO4 -> Fe2(SO4)3 + KCl}$$
$$\ce{K^{+1}Cl^{+5}O^{-6}3 + Fe^{+2}S^{+6}O^{-8}\_4 + H^{+2}2S^{+6}O^{-8}4 -> Fe^{+6}2(S^{+6}O^{-8}4)3 + K^{+1}Cl^{-1}}$$


When I analyze this I can see the following things: 


* Fe lost some electrons, it went from +2 to +6
* Cl went from +1 to -1: a gain of elecetrons


**But**
* I see something happened to the SO ions as well: on the left side you have two times $S^{+6}O^{-8}\_4$ and on the right three times so something changed here as well. What happened? Do I have to take this into consideration as well for the calculation? And on top of that $O\_3$ on the left side disappeared.


My current guess is that you never have to look at the change in oxidation state of oxygen atoms. Is that correct?


