How did you get your EmS so high?

I have done all the main quests. I cured the genenopage, sided with quarians, disarmed the bombs, bomb the monestary, helped the asari, saved jack, saved Jacob, saved a colony, found a chemical burn for the turians, sided with the batarians, got the volus bomb, met up with Zaeed. I sadly never found Kasumi or Kelly. Dr. Chawkas is on broad. I still have side quests to do where i scan the planets. The headquarters is my only mission left, which I know is the last one..

And I only have 4300. and yes I know to do multiplayer. so what am I doing wrong?