14 days ban after one game report?

So my account has been banned for 14 days after a single report? The adc i was plyaing with started blaming and flaming me, the support my main role. He even went as far as calling me a f**** idiot but i didnt go so low. I just left the lane and started roaming and ganking other lanes. Now my account has been banned after one simple report. Its funny how riot doesnt look at who started the flame and simply bans you after one game with not a single warning. Maybe riot should look in to who starts the flames and punish those that ruin the game. I cant keep my cool when someone makes a mistake, blames me and calls me names. Yet i dont call names back, i just leave the lane and keep playing and this is how riot handles this. Here is the pic of my ban. As you can see a simple 1 game report gets you 14 days ban. https://imgur.com/CFfr00F
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