I woke up shattered at 6:05am, I thought I'll be leaving by 6:30am but didn't leave till 7:10am and then I was so tired that cycling got a bit hard...I didn't get lost on the route or anything- to the event, I planned my routes in advance on strava to follow.How come you were so late ? Misjudged the pace ?
I'd set myself little goals - go visit a castle or something 40 miles away or something. Research a decent cycling cafe and ride there.
You do need to be able to fix punctures. Look it up on YouTube and practice on your front wheel first.
Get that sorted and then you can practice on the rear wheel.
Of your bike is looked after and cleaned I reckon 95% of incidents are punctures.
I tried practising before with a video tutorial- but couldn't fit the tyre around the rim well so it kept rubbing..so had to get the bike shop to fix it..