When your baby is a little older, you can start adding pumping to your daily routine. While it's not necessary, it's comforting to have a little bit of a stash of milk built up before you return to work. Warning - be sure to read this page on smart use of your freezer stash!
You must file a tax return if your net earnings from self-employment were $400 or more. So consider this: you may be 36 years old, single and make less than $10,000 per year in regular employment income, but if you have a side business that nets you more than $400, you will need to file a federal tax return.
First, in order to collect a refund, a tax return must be filed with the IRS no later than three years from the due date of the return. After that, the money gets absorbed by the treasury, so you should stay on top of it. There is no penalty for filing a late return if you qualify for a refund.