Trying to lock a mortgage

Hi,

I got back from Disney and had fun. My wife's father is not doing well and I've had to take care of the kids, so I am taking a break from trading. Still working on analyzing my past mistakes. One thing I am doing is trying to lock in a mortgage at a good rate. A friend who is a broker told me about the ticker that mortgage rates are associated with (at least partially): TNX. I am currently doing some plots and sure enough this seems to correspond with rates. I was trying to lock in a mortgage at 5.00 or less today for a super conforming, and rates gapped up badly, so waiting until tommorow.