What Causes Stomach Ache After Having C-section Delivery?

Hi. I had my baby Cde the 8th last year so am almost 7 weeks and istill have some pain Iin my lower stomage. I want to do my house cleand but seems That the pain get worse and l still have some liquid out of my vagina, is that normal? And l sshouldn't be able to do a house cleaning work yet?