Should I up my minimum bet

Just started in the casino's three days ago. First trip after three months of practice!

I have been playing now for hours and hours and hours, days really.
I started, with a BR OF $3500 at $10 minimum, doubling my bet at a tc of 1, and bet $40 at tc of 2 or higher. It's been three day's now and I have a BR of $7200.

My question is... should I raise my minimum to $20 now and have a top bet of $80. or would that bring to much heat.
Also I have picked up a few players cards... should I continue to use them or lose them.
Not much on comps and I heard that the players cards will hurt me... if I count.
Any information would be great!