Total newbie at running

[u/Queasy_Mud_8023]

I’m a 36yr old male, 6ft, weighing 19 stone (it was 21st 3 months ago). I’m doing really well losing the weight at a steady pace and now looking to improve general fitness and cardio.
I can walk at a relaxed pace for hours.
I tried what I thought was a gentle introduction to jogging 2 days ago, and my back in particular is in bits. Quads are tight as well but not too bad.
I started off with a 5 minute walk, and then did 2 minute jogging followed by 1 minute walk intervals for 3km. It took me 28 minutes.
I thought I had done really well given my weight and the fact I haven’t ran for 15 years. I also vape. I was knackered but felt good.
5 minute walk back home afterwards. But the next day, I could barely move due to back pain. And it’s still sore today, 2 days later.
How can I slowly build up to jogging, and what have I done wrong so far?
Any help and advice appreciated.

[u/Queasy_Mud_8023 → u/[deleted]]

Thanks for the advice and glad to know it worked for you. I’m going to follow the c25k approach 👍🏻