multi planned work outs sequence

Just my opinion... BUT, unless it calls for a brick (or if they specifically say the order), it doesn't matter when you do them in the day.  I'm sure it's better to do a high intensity before a recovery, but I say, get them in when you can.

It's hard enough planning your day around training, so get them in when it's most convenient for you.

Sometimes I do one in the morning, one in the evening, one at lunch and one at night, etc.  Whenever it works for you.

The order really doesn't matter. However they fit into your day should be the primary guide.

Also, unless the plan specifically calls for a brick, it isn't. They are two distinct workouts.

As to what to put between them, at least a couple hours and a decent meal is best. A nap in between isn't a bad idea if you can swing it, but I don't know many people who can work that in. This doesn't always work, though. I've had those days where the only way to get a swim and run in is to do them both at the Y one after the other. We're busy. It happens.

 As to why you crashed on the run, if your logs are any indication, you've ramped up your volume and probably intensity pretty quickly. Too much too soon is a great way to get injured. Your body may be trying to tell you to ease off a bit.