why is my Cframed brick going so fast, can you guys tell me?

You're moving your brick 2 radians (about 114 degrees) in the y-axis every fraction of a second, which is a really big leap. You could do the following:

brick = script.Parent
while wait() do 
    brick.CFrame = brick.CFrame * CFrame.fromEulerAnglesXYZ(0 ,math.rad(1),0)
end

But I prefer to do the following:

brick = script.Parent

--runs the loop every 0.03 seconds (the default wait time)
while wait() do 
    --rotate the brick 1 degree in the x axis
    brick.CFrame = brick.CFrame * CFrame.Angles(math.rad(1), 0, 0)
end

math.rad() converts a degree to a radian which is what the functions take as parameters