If you have to breast feed every two hours, and stroked the baby's back, you will not have enough sleep. You will be so tired that you don't want to do anything at all.
I took a bath and washed my hair a few hours after I gave birth. It is so dirty, how can you not use water to spray. There is soap and shampoo with ginger, and you must dry your hair asap with a hair dryer...cannot afford to catch a cold.
They didn't take a bath in the old days cause the water in the well was full of germs.
I walked about, sat and even went to a park to get some sunshine for me and the baby. I don't think the uterus falls so easily. Ask a doctor/nurse, not old ladies who believe in non-scientific methods.