Sewing Machine Update

You may recall my previous post about my sewing machine breaking, the rude behavior at the sewing store and the guy who supposedly fixed it.  When I returned with the machine I did try it and it sounded good and seemed to work fine.  I commented on the short amount of time it took to fix my machine but I was glad it didn't cost more than it did.  I've been busy with shopping and other chores but yesterday I decided I better get to work on my project.  At first it was going very smoothly, then it froze up like it did before.  I do remember telling the sewing lady that this issue and the thread tension problem came and went.  As long as it goes in a timely fashion, I guess I can deal with that.  However, more things started to happen with my bobbin so I took it out and found the one side was bent and that was what was making it jam up.  It still seems like the tension is not on track but it's working.  Also the last thing to happen was my needle falling out.  I realize I've been pulling a lot of material through that small space under my machine and theoretically the screw holding the needle could loosen, but I know he replaced the needle and this has never, I repeat, never happened to me before.  So I replaced the bobbin and screwed the needle in, tighter this time.  But now I'm thinking  "Did he really service my machine and fix the problem or did he do a bunch of little things and as long as it seemed to be working, didn't dig any deeper?"  I think he just put the thread tension knob back together despite me telling Kelly that it wasn't working before I took it apart.  Why did that bobbin get so bent anyway and will it do it again?  He was a nice enough guy but if I take my machine to another store next time I need it fixed, will I get the same guy?  All I have to say is thank goodness I didn't have to pay more than I did however another $50-$100 and the assurance my machine was good to go would be priceless!