How to get rid of red hair!?

Two days ago i dyed my hair and my extensions a semi red mahogany colour at a salon. It cost 100 euro and i hate it! It just glows red and is too bright. I need to fix it before next week :/ i heard ash browns cover reds so would a semi ash brown cover it. I need to do it myself because i can't afford another trip to the salon :( i really need help!