Am I just dealing with pain, or the possibility of making this injury worse?

I strained my glut/hamstring 2 1/2 weeks ago, playing Ultimate frisbee. I lunged and felt pain shoot down from my butt, down my hamstring. It has improved to the point where I just tested it and was able to run around the block without excessive pain. I could definitely feel my butt with each step, and there was still plenty of pain. But I think it may be manageable to start playing again.

I’m thinking of getting back on the Frisbee field tonight. Any idea whether this kind of pull or strain is something that can be easily re-injured? Or is the pain the only thing I need to worry about?