I used to feel like this a lot when mine were small, and still now sometimes even though they are both school age.
I would advise getting out of the house. Even if the idea seems like a mammoth task, do it. I always used to feel infinitely better for getting out of the house.
Also as PP have said, pat yourself on the back for all the achievements. Up, dressed and fed. Do a small tidying job that will alleviated a little more stress - empty the bin, do the dishes, just one thing that will make a difference.
Then head on out. Take your time, push through, get a walk and some fresh air, don't sweat it if takes ages to achieve or you don't particularly enjoy it, just go with it, and by the time you get back you can give yourself another pat on the back and hopefully the mood will have shifted a little.
But definitely push to see HV and/or GP for some extra support 