Problems encountered on Nokia 5800

I already had problem with my New Nokia 5800 after I bought this phone for 3 days!!
What an annoying thing!
The first problem I encountered was that the phone was restarted it self every time I went to the Gallery...It also happened when I went open Gallery again to send MMS message.Then when I was playing the music from the music gallery I couldn't turn up or turn down the volume! I couldn't even deleted any songs from there!!It said General error!But when I went to the memory card and played the music there I could turn up and turn down the volume. I could delete song files from there too. But the deleted files still remained on the music gallery. And I couldn't play it either.I didn't know what was wrong with this phone!
It was driving me mad. Well...I still have the warranty though but I didn't want to return it and found out that my phone is already broken!
No way! Because I love this phone..Never want any phone like this one...
Then I restarted the phone and it was getting worse.I couldn't use any internet connection from my phone!
Then I intended to upgrade my phone firmware (from Nokia official site), but when I checked it, it was already updated (V20)
Then it said that I could even reinstall the firmware again if I wished. And I did that unless my phone wouldn't work anymore..
Then I downloaded the software and followed all instructions...but every time I came to the last part of the re installation it was stucked. The phone is off and was disconnected from the PC.It happened many times.Although the screen said that it was normal for the phone to get disconnected during the process but it was different.I waited 15 minutes for the process to complete, but no success. I tried again another 15 minutes and again and again.But none of them were succeed!
I was crazy about that!Then I thought that bringing the phone to Nokia care would be the best way.
I couldn't even sleep all night. I tried to figure out what was wrong with my phone.
I was thinking the the software of this phone made this phone didn't work properly. i didn't think of anything else.
Then my boyfriend asked me to take out the memory card from the phone!
Di you know what happened??
The phone went back to normal again.I tried to send 1 music files to the phone and played it and test the volume and everything worked normally. nothing wrong with the phone without the memory card. So I assumed that the problem was in the memory card. I didn't know whether it broken or anything. Then I decided to reformat the memory card. Of course I lost all my data there because I didn'd back it up. But it didn't matter. I had them all on my PC.
After reformating the card, I put it inside again and send some data and tired them all, and it was like a miracele to find out that it seemed that nothing happened to the phone. The phone is like a brand new phone again!
And I hope that it will stay well forever...
Fiuh...what a nightmare!