Started running and can’t feel legs...

[Fruitbatdancer]

So embarrassing as it’s not even running, just walking fast! I am v overweight (first time in ever written that) post baby fat and comfort eating that’s been around for 4 years.
Just bought a treadmill (I have never cercised) Can’t continue as I am, need to get fit and healthy for my son. Did 20 mins at 4.5 km/h an hour this morning. Could barely walk when I got off. Thought I was breaking myself in gently but 15 hours later legs are aching a LOT..
My Aibu is is this normal? Am I just way too unfit? I’m ready for another 20 mins tomorrow (hopefully a bit faster). Will it get easier? I don’t want to fall off treadmill! Should I run for 2 mins instead of fast walk for 20? Would that be better?
I’m trying to eat right too, but I have a lot to shift. Help!

Don't push yourself too fast too soon - listen to your body!

Look up DOMs. Also you shouldnt be walking fast. You should be starting slowly for short periods of 5 minutes and then increase in length gradually. When you can do 30 minutes easy then you increase your speed.

And when I say gradually I mean over a period of weeks.

Keep doing what you’re doing right now as if you do too much too soon you’ll put yourself off. You’ll see results, well done for starting.
I used to go for a brisk walk for half an hour every day and lost 4 stone by doing that. Keep up the good work!

Try couch to 5k. It's a gentle way of getting you running, you can download an app, I used the nhs one, it's walking and running intervals that builds you up slowly and (almost) painlessly.

Really? Blimey. I thought I was taking it easy! I was gutted I only managed 20 mins!! Off to google DOMS

Another vote for couch to 5k

Thanks off to download app...
ps I have DOMS (proud 😬)

Another couch to 5k vote here, I've done it that way, from not exercising in over 10 years, to running for 16 minutes. Little bits at a time is better, this way you do 1 min running, 2 walking for half an hour the first week over 3 sessions, then upping your running time steadily till you're running for 30 minutes after 10 weeks. It's good, I tried it with a beginners running club, but I can do it in th heat we've had this summer. Do it at your own pace and you'll get there :)