Stuck

While everything has been going really great with getting to the gym and doing my workouts and whatnot, I seem to be stuck in a rut as far as my weight going down.  Every time I get down to a certain number, the next day I'm back up where I was the previous day.  I think I've lost the same 2 pounds over and over again for the last two weeks and I have no idea why I can't just break the barrier and keep losing weight.  While I'm as motivated as ever with the exercise, it's just so incredibly aggravating to be seemingly unable to break the barrier I'm at.

I have been running at least three times weekly, and for progressively longer amounts of time.  I haven't really been doing strength training because I'm not nearly as enthusiastic about it as I am about running.  I should probably start doing some sort of strength training, but I'm hesitant to do that because I feel like every time I do, I only gain weight.  Is there some happy medium I'm missing?

I am all ears and if anyone has any advice for me, I would greatly, greatly appreciate it.

Thanks in advance!

Tschüss!