Should I lock in Mortgage Interest Rate Today?

Refinancing over the last 4 months has literally been my nemesis and it's like I'm being taunted by a greater force. I've been on the cusp four times and every one some observed event trumped sealing the deal: Grandparent's death, wife needs gall bladder surgery, someone promises great rate and it falls though, etc.

I finally got my shite together this week. Great deal, pulling the plug. Internet goes out at my office yesterday afternoon. Never happened before, out for an hour and a half. I finally finish my application but too late to be processed. I'm worried. Well of course, self-fulfilling prophecy of my paranoia occurs and rates have their single biggest overnight jump in 2.5 years. Nearly 1/1000 scenario comes true as a result of this cooked jobs reports. Awesome.

So, do I lock this afternoon or wait till Monday/Tuesday. I'm thinking about waiting, but everything I do is wrong. thanks for listening.