Iphone 4 volume is not working unless I plug in my headphones?

I can't listen to music, youtube vids, vines, and instagram videos without headphones plugged in. #thestruggle

Can someone help me out? Should I go to the apple store? I need options about what I should do.

Sometimes my iphone 4 does the same thing. I would have to go to the music app and adjust the volume from there. However, it's easier to do this: go to settings, general, accessibility, then click on the "triple-click home" button and select "assistive touch." Now whenever you triple-click your home button a small icon will pop up from which you can adjust your volume.

There has to be a way to silence the phone and I suggest the silence button is activated.