Everyday obligation for a single mom is almost the same as they are married: coping with sleeplessness, looking for child care, paying bills. So,are you up for the challenge? The longer answer will be that the parenthood is the biggest engagement you'll ever face. But that's true even if you're married! You will surpass the fear.
One way to acquire serenity like this is take life one step at a time. Focus on giving birth, be devoted for a newborn, Then looking for work and daycare. Forget also long term planning or system during those first sleep-deprived weeks. Of course you'll still have fears, so talk to your friends and family who give you good advice and who don't panic.
There are a lot of single moms who get honest, substantial child support payments from the baby's father. But if reading that sentence makes you laugh, you're probably one of the most women who have became the breadwinner. I salute you!