iPhone 4 not turning on.

My iPhone 4 was on 80% this morning, when i put it in my pocket. When it was taken out, it didn't turn on. I tried plugging it in to charge, plugging it into my Mac, and pressing the lock button for a while to see if it will unlock.

I had a look around google, and people are saying that if you press the home button and the lock button at the same time for about half a minute works, hoever my home button is broken, so i cannot do that.

Does any one have an ideas, or should i talk to the apple Genius bar?