Hi R.,
You will be just fine :O) I know it's scary to be "the mom" when you've never had to do it before, but now you have to do it alone. You can do it, R. :o)
Sure you want to make your baby entertained, but it doesn't mean that you devise all these plans to entertain your precious baby. Your baby will be entertained by watching you!
With my 2nd baby, I made sur to make MY chores a part of everyday life. This way he knew, even as a baby, mommy had to go "rotate the laundry". With my 1st son, my world revovled around him :O) I dropped everything for his "whimper" or needs. But, doing that can be exhausting on mommy.
My suggestion, develope a morning routine that gets YOUR chores done, because babies are happiest to entertain themselves in the morning. Then, after your babies nap, you are "stress-free" because your chores are done, and you are dressed :O) The rest of your time is to play with your baby.
R., the trick to being a SAHM is to "juggle" life with children. You know, the laundry, dishes, bills, etc... The sooner you try to implement a routine for yourself, the sooner your baby will expect you to do things for yourself.
You cannot get overwhelmed, because if your baby is only 5 months old, then you still have 2 years to practice being a SAHM according to my life :O) That's about how long it took me to figure it all out....maybe even longer!
~N. :O)