Lenovo crashed randomly thrice this week. The screen each time just went black and the phone would not turn back on afterwards when power button was pressed and held; however, after a few hours it would turn on by itself. When the phone is in a such a "blackout" (sorry for a lack of a better word) and the power button is pressed and held the screen flashes for a short second but then becomes black again. Before it crashes, the phone does not freeze or get stuck, i.e the phone is running fine before it just blacks out. The phone runs quite smoothly otherwise. RAM isn't the problem as well.
I don't know if this is related or not but the apps being used when the crash occurred were youtube and two gaming apps, including Cheating Tom.
What should I do? Should the phone be taken to an expert or can I do something to fix it myself?