2 day period

I have a question my period started on July 10 I would say it was farely heavy yesterday as well then this morning I go to the restroom to change my tampon since I'd slept for about 4 1/2 hours and it appears like my period has ended my period normally lasts 5 days I read where women have found out that they are pregnant after this happening to them but that's not possible for me since I haven't had sex since March just curios if this has happened to others and if I should worry now or wait until my next period and see if it does the same before I start to worry