Just got my hair colour corrected, can I put colour on it?

my hair was all black, i got it bleached 2 weeks ago and he put colour over it to fix it and blend it but the colour is too dark.. i was charged 120 and he said to make it the colour i want i'd have to go in 2 more times and pay him 40 bux each time and i dont wana go back there cause i feel like he should have gotten it right the first time..... so is it safe for me to BOX colour my hair the lighter colour that i wanted? or will i ruin it?