Hard reset issue

[Rose640]

So my Lumia 640 started acting weird today, it would ' resume ' everywhere, even in the lock screen. I performed more than few soft resets, both with the buttons and removing the battery, it wasn't helping, so I thought I had to hard reset it. Now I checked if my phone data was backed up, it was, so I hard reset it. After couple of minutes it was done. That's when I freaked out, it was all erased, all the stuff, after five minutes or so it loaded my photos and music from my SD card, which I can't say for the apps too. The phone says the apps do exist on my phone, that is ' from different phone ', and they can't be loaded again nor I can install new apps until I delete these ones. Now do I really have to erase all my apps and download them again, like 30ishn of them? Please don't say that.
P.S. Don't install tetra lock screen app,I think my phone went nuts because of it.

 

[vipme]

Yes, you need to download all the apps again. And also format the SD card, but first coppy the photos, music and videos off it.

 

[Rose640]

Why should I format my SD card when I have full access to my previous photos and music.
One more question, what's in the ' others' folder, can't remember having anything that my phone can't open.