Day care job making me 2nd guess being a mom

I've always wanted to be a mother. I used to love being around kids and taking care of them. My fiance and I have been ttc for awhile now and I just started at a job at a daycare center and already want to quit...I'm finding myself having very low patience with the children. And all I can think is "I'm really getting paid 9.50 an hour to change all these dirty diapers and listen to these babies scream?!" Does this mean I shouldn't continue to try and have a baby of my own?! I feel like a terrible person...