Possessed iPhone 6 and How to Fix It?

Since two days ago, my iPhone 6 was getting weird. It couldn't work well. At the first day, it was frozen. When I tried to switch the screen, it didn't work. However, I didn't care much and just waited for like ten minutes, then my iPhone works normally. On the second day, it started possessed again. Sometimes when I was typing, it typed what I didn't type. Well, it was just "sometimes". When I was trying to sleep, shockingly my iPhone downloaded and played a game by itself. 

Today, my iPhone getting crazier. It is kinda frustrated to deal with this possessed iPhone. It tapped randomly, typed by itself, opened application randomly, and played youtube and move it to the other youtube channel. Even, I was struggling to turn my iPhone off. --" 

I have tried many things to fix it:

1. Reset my iPhone. I pressed the power and home button. Then, I waited until the Apple logo appears. After it went on booting, it remained moving randomly. Apparently, resetting didn't work for my iPhone.

2. I tapped setting, chose General -> Reset -> Reset All Settings. Poorly, my phone getting possessed harder.

3. I did a hard reset: General -> Reset -> Erase All Content and Settings. (If you have data you want to keep, you have to back up the data by using your iTunes or iCloud account first). Unfortunately, this thing didn't help my phone. (I competed with my iPhone brutally when I had to choose the language, the region where I live, Apple ID and my password.)

4. I tried to turn my iPhone off. After that, I took a hair dryer and blew my iPhone up and down (for five minutes). Then, place my iPhone in front of a mini fan. 

After 10 minutes, I turned my iPhone. Apparently, this way made my iPhone being more tamed. Then, I realize maybe my iPhone 6 is freezing. :(

I turned it off, took a hairdryer and blew my iPhone again, longer. Then, I placed it inside the blanket. After a half of hour, I turned my iPhone on, then wallaaaaa apparently this step works on my iPhone. :D 

(Even though after I turned my iPhone on, it looks tapped randomly just for twice, well it can be said my iPhone is getting better). 

I am not sure the reason why my iPhone getting possessed, but it might be because of the extreme weather. A week ago, the snowfall fell into my iPhone. A couple days ago, some teardrops dropped onto my iPhone. I live in Taiwan which is now is winter season, and there is no heater in my apartment. I think it is not only because of the cold but also the humidity. It is so humid in here. Every night, I saw my iPhone has dew on top of its screen, and my iPhone was very cold if I hold it. (Poor iPhone, maybe it feels cold and lonely :p).

I think if it is summer, your iPhone getting hot and has same problems with mine, you just need to cover it in order to protect it from the extreme weather.

EDIT: MY PHONE HAS BEEN FIXED. THE PROBLEM WAS ON ITS "IC".