Well done dude! great effort! also just started again this year and it's a challenge! but keep putting one foot in front of the other and you'll get there! Look at me, I'm now doing a 5km uncomfortably after 8 months lol!
If there was another way as effective I would use it.
100% nothing is as effective as running!
I finished 5k just once, and managed to injure my calf on the home run. That's what you get for trying to sprint.
Man that is rough. Gotta go slow before you try to go full rocky! Need to get a Mickey to ride behind you in case this happens again! Baby steps. If you keep at it. I'm sure you can get there again and conquer it. Just listen to your body when it says stop! I find music helps me not focus on the run do much. The right tunes make all the difference! Keen to see your next run. I'm routing for you!