What in the world is up with this 14.3 update???

I use an iPhone 7 that I got two years ago for Christmas and before I got this update my phones been completely fine. No casualties whatsoever with my battery. A few days ago while building a puzzle I saw that I needed an update and was like “Hm, why not.” So I update my phone. The next day my phone’s battery starts to drain quicker than normal, my phone lags and is slow, apps crash, some apps can’t be downloaded, all kinds of problems occur, etc etc. I power off my phone. Didn’t work. I delete some apps. Didn’t work either. I check my phone storage a lot so that’s not the problem. I check my peak performance and everything seems to be fine. A few days pass and today I start to get worried if viruses are on my phone. So I check the web, but I see that iPhone viruses are rare, so that obviously wasn’t the problem. I go to check my battery peak performance again and suggestions says that I have been using my phone more often after I got an update.

Now I know that this is bull crap because I use my phone almost all day everyday. Even at concerning hours at night. I generally start to become concerned with this so I go on the web and look up what’s happening. It seems like many other people have been having the exact same issues. It looks like Apple’s updates are become more and more crap too. The thing that’s even EVEN more crap is the fact that we can’t downgrade our phones either or do anything about it. I’d like to know what in the world is going on, because if my phone keeps on working crappily like this, I’m going to get even more worried and panic about it.