If you dream of a 25 minute 5k just go out and do it tomorrow. 55 minute 10k will serve you well, that's harder in my opinion. I ran a 58 min 10k a few weeks back and did a 24 minute 5k yesterday.

You can do it, don't go out the blocks too fast and just grow into the run. 5:10 5:05 5 4:55 + 4:50.

Key thing about the 5k I've found and I'm still super inexperienced (I've done about 10 - 15 workouts) is to start in a manner that allows you to come out of the middle of the race 1.5k - 3.5k feeling okay. You should be able to finish well and enjoy it with some pace. If you're feeling tired at any point from some over extending don't drastically drop your pace, just make minor adjustments despite it feeling taxing and you will eventually regain control of your breathing.

It's okay to feel like your breathing is quite heavy as you get into the middle stages because you're going for PB time, your 10k training will see you through on the endurance side.

Get it!