Changed iPhone battery, now home button is touchy?

I changed iPhone 6 battery, it's working, but now the home button does not turn the screen on from being dark, but once I get the screen turned on (by using lock button) and try pressing fingerprint on it a couple times, it will eventually unlock. Also, the lock button will not always turn the screen on when screen is dark- It takes a couple of tries. What could I have bumped while inside changing the battery? I've tried tightening and loosening the screws to the cover over the button, I've tried reattaching the screen cords to the other half of the phone etc, without luck so far.

IPhone message app keeps crashing when I try to get to the top of the messages?

IPhone message app keeps crashing when I try to get to the top of the messages? - 1

Added (1). I'm trying to do something special for my girlfriends birthday and it involves finding the texts from the day I asked her out. This was about 4 months so we have texted a lot since. I have gotten a little over 3 months in several times and every time the messages app crashes. I feel like its due to the amount of texts we have, is there anything else I could do like delete other apps/texts on my phone?

My iPhone 6 randomly restarts

My iPhone 6 screen has been turning a random color (red or blue) and then it shows an apple logo then turns on again. It has been happening for a few days now. I throw my phone every once in a while when I get mad (no noticeable damage or cracks because I have a case). Is anyone familiar with this who can help me? The phone is about 2 years old and hasn't had many problems. I'm currently on iOS 8.1.2

Does it sound like I've been hacked?

I'm worried my iPhone could have been hacked. No one has had access to it physically but yesterday I received a message from cvs even though I'm not a costumer there. It said to text stop to quit receiving messages so I did. Could that have been a hacker or simply cvs had a wrong number? All my apps are still there and there have been no new ones that I can see. I tried to download a new app today though and it wouldn't go through. Is it probably just bad internet connection? Have I been hacked?

Inner iphone 6s cracked screen?

I dropped my phone and the screen cracked. The screen started glitching and there are a bunch of colors that show up on the screen. It wasn't as bad at first but it got worse. Will it be able to be repaired or do I have to get a new phone? I don't have anything backed up and i don't wanna have to get a new phone.