Unidentified plant

I found this quite small plant down by a small creek in Big Hill Springs park yesterday. This park is NW of Calgary and it was the first time I had ever been there before. A beautiful place to explore! This plant looks like a member of the Mustard family but I'm sure I have never seen it before. I seem to remember that the leaves were very narrow and long. If anyone is able to ID it for me, I would be very grateful!