You got side imaging? Trust your electronics. If it says there is no fish....there is no fish. Keep moving til you find em. I sometimes will fish on a gut feeling even tho my graph says no fish, and that has yet to be a good decision. Its hard to NOT go with what I know OR with what worked yesterday. If that thing says no fish...it means it!

P.s it sounds like you did everything correct. Sometimes it just doesn't work out and that is what makes it fun.
GOODLUCK!