Ladies! So I finally pumped enough not only for my husband to take the first night shift but an extra bottle :•) but,…

Ladies! So I finally pumped enough not only for my husband to take the first night shift but an extra bottle :•) but, how do I go about this? I read that once in the fridge it's good for about 5 days and to warm it up you can use a cup with warm water, but how long after warming it up do I have to discard it? If anyone can answer, thank you so much!