Photoshop gradient is destroying me!

Hi, I'm new to photoshop and my will is being absolutely destroyed by a problem I'm having with a gradient.
I've given the foreground and background 2 different shades of blue and clicked on a circular gradient. In the top left of the screen the gradient box shows a blue to blue transition.
BUT, in the foreground and background color boxes in the toolbox the shades are black and grey, EVEN THOUGH WHEN I CLICK ON THEM THE COLOR COMES UP AS THE BLUE I PICKED!
I'm sure there's like, 1 single box I need to check to fix it but I've been banging my head against my screen for over an hour now and I can't find it. Can anyone please help me?

Here's a screenshot of what I'm dealing with. I want color but it's just giving me black and grey

don't change the color in the gradient at the top. Just choose your background color then push x and choose your foreground color. then use the tool.

if you change your foreground and background colors on the bottom on the "tools" menu the top gradient color will change to those two colors automatically.

Thank you very much for the help, I'm appreciating it.
I'm not having any luck so far though. For some reason, when I click on the foreground color the color picker window comes up and I pick my color, but then when I hit OK the foreground color continues to stay grey.
Same with the background color.
In the Color Picker dialogue box it's fine, but for some reason its not changing the colors.

oh you're probably working in a B&W workspace.

at the top go to Image > mode > RGB color

You're right!
Thanks for the help man, you're a life saver!