I was going to come in here and say what jrbeauty76 just said. Girl get out of that Mac store!!! LOL!
I know MAC was what I used when I was first getting into foundations and it seems to be the measure to which everyone figures out their skintone, but I would agree on just trying different foundations till you find one that's good for you. I haven't used a Mac foundation in years, they are soooo just... ugh, especially when there are TONS of others to try.
Don't be afraid to ask for samples (are you near a Sephora or Ulta??) of a few different shades of a brand until you find something that looks good on you. Wear it the entire day and see how it does giving you what you want. Matte/dewy finish. Light/medium/full coverage, etc. I also agree with the pink undertones, so you're a cool lady. Look for foundations that look a little peachy and cool as opposed to those with yellow/warm undertones. And drugstore foundations are MORE than ok to try out as well. Not sure if you're in the US or UK, I know in the UK folks don't usually return makeup, but here, we can and I DO. If it's not working for me back to the store it goes. I know it's difficult for them to have samples out in a drugstore, so they have to expect that if someone buys a foundation that's not the right shade because they had to guess, then they should also know that returns can and will happen. I have a mix of foundations from Sephora, the drugstore and online. I don't discriminate and use different ones on different days.
I's also suggest trying one of the BB creams to start. AND I'd recommend this website:
If you've used foundations in the past that were a good GOOD match, add them to your findation "profile" and it will show you other foundations from different companies that other people who have used what you use, have found to be a good match. The site isn't always 100%, the more you add, the better it will be at matching you, but at least you can get a general guideline.