IPhone 4s speaker sometimes works sometimes doesn't?

I was watching a video on my iPhone all of the sudden it stopped playing the sound out of the speaker. I tried the silent button in the side, doesn't change it. When I press the up volume button it puts the box on the screen but there's no volume bar on it tellin you what volume it's at. When I go to my music and hit play the volume bar on the bottom is light grey (can't change it). I can ask Siri a question and when she answers it comes out of the speaker on the bottom so I know it works it just won't play any of sounds.
I've tried my settings when I play my ringtone it plays through the speaker but my text tone won't play. When I pull the settings up from the bottom of the phone (flashlight calculator flight mode etc) there's no volume option there either when their usually is.
My lock button is broken so I can't reset my phone or turn it off and on again to see if that will work. I let the battery run out and plugged it in to the doc it turned on and would play music when I took it off and tried to play music. Then I plugged it in to keep charging it and now it won't play sound on videos or music again.
I've cleaned out where the phone plugs in thinking maybe it thinks it's on a doc but that hasn't changed anything either.

Try smashing it.