Many times an uploaded a video or photo will initially show up as being too large or too small on the page. This can easily be resized.
Simply put your cursor inside the video or photo window, hold down your left mouse button and move the mouse about 1/2 inch.
This results in the window becoming highlighted. There will be small little squares on the corners of that widow. Grab one of those small little squares and drag it to the size you want.