Images are too large - xamarin.forms

Question

I have two images, one is a transparent TestTube.png (25 Width, 150 Height) and the other image is a Block.png (10 Width, 10 Height) that goes on "inside" of the test tube image.
Below is what I WANT my Screen View to look like, these would be just two different PNG's on top of each other a bunch of times.
|X| |X| |X|
|X| |X| |X|
|X| |X| |X|
|X| |X| |X|
|X| |X| |X|
|X| |X| |X|
And this is roughly what it looks like now
| | | |
XXXXX XXXXX
XXXXX XXXXX
XXXXX XXXXX
| | | |
The Block.png is WAY too large, and I'm not sure how to make it smaller. Putting in a smaller image size does not seem to work.
I'm trying to use Grids to do this but I'm not sure if this is necessary or not.
function void doStuff()
{
StackLayout objLayout = new StackLayout();
Grid objGrid = new Grid();
//Assign the grid layout two Rows and two Columns
//Semi Psuedo Code
foreach(column in grid)
{
TestTubeImage = new Image { Source = "tube.png", WidthRequest = 25, HeightRequest = 150 }; }
BlockImage = new Image { Source = "block.png", WidthRequest = 10, HeightRequest = 10 }; }
objGrid.Children.Add(TestTubeImage, x, y);
objGrid.Children.Add(BlockImage, x, y);
}
objLayout.Children.Add(objGrid);
Content = objLayout;
}