Engine Coolant PLEASE HELP

I was driving today and the check coolant light came on.  I was near an auto parts store, so I bought some coolant because it was low.  Later on my friend said I can only put in Dex-Cool.  I didnt know this, and I put in Prestone50/50 mix, which says can be used in any model and can be mixed with any color.  I assume that it's not a big deal.  Just wondering if anybody has done this, and if I need to replace all the coolant in there tomorrow morning, or if I'm fine driving with it.  96 DeVille by the way.  Also, what temperature does your engine usually run at.  Mine is usually between 180-200 F.
 
Thanks

I believe Prestone has worked with General Motors and that GM has approved the use of Prestone. The container will disclose this.

Owner's manual indicates normal operating range to be 180 to 200 for the Northstar.

Thanks.  As far as the container says, it can be mixed with any car and any color.  I just wasnt sure, because I've been reading a lot of stuff online about not mixing the two kinds, or not using one after using the other.  (the green prestone with the red dexcool)

I think the colour is artifcial. I went to the Prestone web site and it says you can use that coolant you bought in all of todays vehicles regardless of colour, it also mentions special inhibitors for aluminum engines and radiators. The site also states that the oranage/red DEX Cool is a registered trademark of GM.