Why is My iPhone is getting hot?

When I charge my iPhone I normally am still on it or it's in my bed with me and it gets so hot. I've only had it for a month! What is going on
It's a Verizon iPhone 5s

You need to contact Apple since it's only a month old, it'll be under their warranty.

When you charge evry phone it will heat. Even my phone htc 1 m8 also heat when charging.
do not use your phone while charging sometimes it will explode
i saw in news too

Edit: make this clearer, downloading drains the battery so has to be on charge when downloading but that's only time it ever gets hot. Makes me think the processors working harder than should be.

I've got a galaxy so not sure much help but mine gets super hot when downloading huge files. I was thinking it's the processor.

Well, wendogscreate is right, if the device is a month old it is still covered, the device comes with a 1 year limited warranty and that covers any issue that you have that is not your fault.
That being said, you do not need to contact us because there's nothing wrong with your phone. Yes it is very small, but despite its size, for all intents and purposes, it is essentially a computer that you can put in your pocket. I'm sure you have a computer and I'm sure you know that computers get hot. So do cell phones. They get warm when they are charging and they can get warm when you are using it. So when you are doing 2 things that cause the device to heat up at the same time it is going to get hotter than you might expect. There's nothing wrong with it. If you end up having the problem where the battery begins to swell and it looks like the phone is being pushed apart from the inside out, or if it gets so hot that you can't touch it, then you can call us. And for what its worth, I do not recommend using the device for extended periods of time while plugged in.

If you are not satisifed with my answer and want to just double check you can call. If you do, just tell the call director to transfer you to iOS. Once you get on the phone with an Advisor just tell them the device is hot and that another advisor recommended that you call and get a diagnositic test ran on the device. Among other things, the test will show if there are any temperature alerts, like if it has ever been to hot to operate without damaging it. The phone number s 1-800-692-7753. Up to you

I had phone with metal cover, however it wasn't an iPhone but I discover some things about it whenever I put it on charge. When I put the phone on couch or on bed which had fabric cover, my phone was getting hot. I was a little worried about that. One day, by change, I put the phone on the glass corner of the wall, and when i checked that it wasn't that much hot. I touched the phone with expectation that it would be hot but it was rather cold. Second day again put the phone on bed and I noticed that the phone was getting hot but when it put it on the glass corner, it became little cold and then normal.