Samsung Galaxy S6 — Phone wont turn on S6 after charging overnight

So I flashed a custom ROM G920x/5x][9.0.0] NexusOS 9.0 for Samsung Galaxy S6. The rom was specifically made for my model. It worked properly installed all my apps from the play store. Now when the battery went down to 0, I plugged it in for charge overnight(around 12:30 am) and I woke up around 10 am. Found at my phone was crazy hot, and I disconnected immediately and let it cool for about an hour. Now the phone won't turn on. I tried holding power and volume down button it didn't work. Please help. When I put it for charge again nothing shows up, but after some time phone starts to heat up again.