In general, a large increase in individual run distance will come with an increased risk of injury. Plenty of people get away with going 5k to 10k, but some don't. I'm glad you got away with it.
A few years ago, when I was Very Fit Indeed, I was regularly running 8-10km 3-4 times a week. I entered a tough trail marathon, fully intending to build up to it properly. Thought it would be a good idea to do an 'easy' marathon before it by way of preparation.
As it turned out, the local annual marathon happened to be a week before the trail marathon, so I entered that.
For various reasons, my training didn't go to plan, so while I was still doing a fair bit of cycling, my running was not going so well.
I still did both marathons, but they nearly killed me. I couldn't run again for months afterwards, and I'm sure that was the start of my general decline in fitness that I have still not properly recovered from five years later - although there have been a number of other factors in that as well.
So yeah, a salutary lesson - don't overdo it, you will pay for it.
I probably would have been fine if I'd just done the 'easy' marathon.
Managed a nice gentle plod round my favourite 8km loop through the woods yesterday evening - first run for a couple of months, in fact - and really enjoyed it. Mainly because I didn't look at my watch once during the run, so had no idea how slow my pace was. I have to remind myself it doesn't matter - just doing the run is the most important thing. Bit of muscle soreness today but with that and the increase in my cycling lately as well, I feel like I'm starting to get the bug again.