LCL injury?

So, I was at a hotel the other day, exercising on a different elliptical which has a much steeper incline than what I normally use...The first night, the outside of my rt knee hurt with every step, but I kept at it. The next morning, I was back, and it hurt a little more, but I thought I'd be able to get 30 minutes in. Anyway at 27.5, there was a searing pain in the outside of my knee, and I almost fell off the machine. Walking when I was carrying my bags was excruciating that day...Once I got home and put my feet up it felt ok, but it hurts a bit when I walk, and stairs are terrible...Today again, stairs are terrible, walking is a little irritating but manageable as long as I don't step wrong and put pressure on the outside of my knee. Do I call the Dr. or just give it time and just not do anything that hurts it?