6 weeks pregnant

I gave birth via c-section 8 months ago and found out that i am currently 6 weeks pregnant. I have been very nauseous(bare-able compared to the 1st pregnancy) and very tired. I just want to sleep all day long. My son threw tantrums nowadays and have been scolding him till he cry. At the end of the day, i will cry when i look at him sleeping on my hands. And im also stressed up because doctors have been saying that its very early for me to get pregnant again. I really feel like im a bad mum.