Your first question has been answered by user user1757436.
I'd like to add something to your second question. First of all, your page is all good and designed nicely. Secondly, contrast is definitely a very important aspekt of web design.
Should you worry about the results from the test of checkmycolours.com?
a, checkmycolours.com
There are many errors reported for color combinations that don't exist on your page.
It takes part of a standard (impossible to consider everything) without any note about restrictions or validity of the results.
b, WACG
I think you realized yourself that the standard has limited usefulness with respect to how certain values are calculated, or what gets labeled "good" or "bad". The most misleading is probably "Color Difference".
Therefore I would only worry if a client specificly asks for WACG compliance.
Font size has a big impact on readability. Since your font size is bigger than normal (good) the results of the tests are not valid (it also states this in the standard).
For future work I'd like to recommend checking your colors with this tool. If the "Lum"-difference of two colors is greater 30% you are good in general. Make it greater 40% if you really want to be sure. Remember that bigger font size lowers the requirement. The disadvantage is that you cannot present a "standards"-document...
Finally, I would change the font color of your contact-form-send-button into white, since you used white in every other case where the cyan-blue is the background color.