what is your team?
i have found the more coins i have won and the better players i have bought one at a time to upgrade the team slowly, the worse i play.
This is why I haven't bought packs, I did the same in 13, had an excellent record with a cheap BPL side then got drawn into wanting the best players and my record turned to crap, and because I'd paid real money to have them it would anger me.
This is the squad I'm using: