Losing coins on 5x5 Deathmatch

I am a new member/player and am absolutely addicted to this game! Thank you! However I seem to be getting worse rather than better...is it better to focus on just a couple of your favorite weapons as far as upgrading/evolving etc..or is that going to bite me in the rear later? I have been trying to keep and upgrade everything and I am beginning to routinely get my ass kicked. I go sometimes 3-5 battles without even registering a kill..also on the event happening right now with the coins:
I have won coins on multiples of battles yet my total shows 0. Is there an entry fee with the coins? Do you lose the built up supply if you lose the match?? I don't understand why coin total is at 0? Thanks so much for ANY advise as to why i suck so badly...

 

Right, first of all welcome aboard. We ideally need to see some screenshots for your current setup and inventory, and then we can advise a little better.
Personally, when I started I focussed on leveling up the weapons I knew I was gonna use right now, and just leveled up others that interested me while they were in my inventory. That way, you won't go into a battle with weaker weapons (level/tier wise) than your usual set up.
Play as many custom matches as you can with folks around your level - it's a zero risk way to work out if you like certain weapons or not, and it'll help you get a feel for the ones you do