You are not crap! You need a bit of a push, but you will get there.
You kids are small and demanding, it is OK to feel overwhelmed.
Are you a list maker? If so write a list of 5 things to get done today.
To sort the house- I would book older child into day care for one extra day a week, then get to grips with giving the house a good clean. But you can do all of this in about an hour. Easy, just blitz it!
Housework
Put a wash on then
Bathroom- clean the loo/sink when kids are in the bath
Kitchen- gat all the dirty dishes into a basin of hot soapy water, meanwhile, wipe the surfaces and sweep the floor.Then wash up.
Living room- go around with an empty laundry basket and fill it with everything that belongs upstairs. Go around again and bin any rubbish. Straighten the cushions. Go around one last time and get all the toys in a box/area
Bedrooms- Take up your filled basket, empty. Make beds, dump clothes in laundry basket. Go round with empty basket and fill with what should be elsewhere. Then empty in the rightful places.
Now your house is tidy.
Lay out your clothes and the kids for tomorrow, pack your changing bag, pack lunches for the kids. Even if you do not go out, all you have to do is make your lunch.
Meal Plan for the week, do a big shop- delivery if you can.
Go and get your hair cut, buy something nice for yourself- new moisturiser, hand cream, magazine.
Lean on your friends.
Do you go to nay baby groups. I used to go to one where the toddlers ran about and the mums used to sit and chat and it was bliss. we would all coo over the little babies. i used to live for one "outing" a day to focus me.
So sorry your kids are poorly. hope things get better soon.