iPhone 4S will not turn on.

iPHONE was on 7% i turned it off too let it charge about 30 mins later i went to turn it back on but it wouldnt turn back on, I then decided to leave it overnight in the morning i tried again and still no luck, i tried using my mams charger and my own and plugging it too laptop but still nothing. I tried holding the sleep/wake button and home button muliple times, ive tried connecting it too iTunes and it doesnt reconise device... its been charging for at least 12 hrs someone please help😟🙂