Light bleeding?

I started lightly bleeding on Sunday night. I had my period 2 weeks before that on the 15th. Still bleeding, but only a little. Not enough to fill a tampon through out the day. Could it be from stress? I started babysitting my niece and nephews 2 weeks ago, and they don't listen to me at all. So I'm constantly getting onto them for everything, and it stresses me out every day to the point where I want to ball my eyes out. Could it also last this long from rough sex? Should I make a Dr appointment? This has never happened before, so I have no idea what to do!