Yeah, I've thought of that before, too!
I think it's one of those things how we all see the world differently...
Essentially 'Light' appears on the 'Electro-Magnetic-Radiation' spectrum, with each colour having a particular frequency...
However, whether the different minds see the same frequency as the same colour... I really don't know...
Colour-blindness, I think, relates to the inability to see particular colour...
Think about a TV screen. The colours are all combinations of Red, Blue and Green (again, I think). If you don't see green, you'll only pick up on combinations of shades of Red and Blue...
I guess Colour-Blindness may be more common than that by working in different ways, like limiting the ability to see particular shades, due to some other phenomena. But, I've never heard of this before. Even then, I still think it possible. And, that kind of thing could lead to someone seeing your Pink as Blue (or more blueish)...
I also want to add a few things that fall into the category of different shades...
This would be qualities of colours, like: 'Brightness', 'Paleness', 'Shininess', & 'Darkness'...
These qualities would compare just to the 'more normal' shades of a colour...
As well as that... I wanted to share the idea, that, if colours can be involved with different sections of the brain, they may well likely make a different message (which would depend on the function of that brain area)...
For example, let's think about a couple of things that would be considered opposites... How about 'Love' and 'Fear'... Okay, they are not complete opposites, as they work in different ways...
Let's consider how they may motivate us to act...
Borrowing the meaning from traffic lights, lets say Green is 'Go ahead' and Red is 'Stop'...
Now let's think of something we are most likely to want to do.
Let's say I am hungry, I have food, the food is good, I have time to eat, etc...
I am most likely going to experience the colour Green in areas where I would love to eat, and Red where I would fear to eat....
Essentially how you feel about something may (in the way that it is communicated within you) come down to what shade of which colours are being used in which brain areas...
I have thought about this a bit and am looking next towards things like: colours in the body (as opposed to brain only), how interactions with other people and objects work (which kind of completes the full message felt by a situation's experience) and trying to narrow down somehow what colours actually mean (without borrowing part of the meaning from a particular brain area they may be used in)...
...again, will write more, as I find out more...