I wanted to know is there a small piece of glass in my foot?

Maybe. If you stepped on glass and aren't sure if there is still a piece inside you should see a podiatrist. Most glass can be seen on an x-ray and can often be removed in the office without having to go to the operating room. If you have swelling, redness, pain and/or drainage these are signs of a possible piece of glass in your foot.
See below. Will need to see a doctor for exam and possible x-ray or ultrasound.