I just recently (about 2 days ago) dyed my dark/medium brown hair light golden brown from a box to achieve a very light brown. This only made it about a shade lighter, not even. So now Im still wanting to make it very light. I'm scared to get another dye because I don't want my hair to turn orange or anything. Any advice?

If you used a permanent colour to dye your hair it won't work even when going lighter as tint (permanent colour) won't lift tint.
I would recommend you go to the salon and save yourself and expensive trip in the long run as if your hair goes wrong it will cost way more than if you had just when in the first place.

You can also as what colour they used in you hair and buy it from a salon suppliers once they have achieved the colour you like. Hope this helps. Dee