In the world of parenting!

I'm a 36 year old mom and I have no idea what I'm doing. Just when I think I am starting to get the hang of things, something else comes up and we are on a whole new phase. By the time lunch rolls around I'm wondering if I took crazy pills instead of vitamins. I only have 2 kids. I have no idea how Jon and Kate do it with their 8!!
My oldest is 4 and my youngest will be 2 in July. I'm always so worried that I'm doing it all wrong, when they grow into adults they will fly away and be a complete mess thanks to all my mistakes as a mom. I hope I'm not the only mother in the world who thinks this way, though I'm sure I'm not.
Some days I wake up in the morning already looking forward to nap time. Is that wrong? I get out of bed and feel as if all the work I have ahead of me will crush me by the end of the day. My never ending job.
But I am thankful. Oh am I thankful. I'm able to be with my girls every day of their lives. I don't miss a moment. We may not always get along, but we love each other and we are so close. We get to snuggle, play, eat snacks together, I get to hear ALL their ideas (if I want it or not!) I get to kiss every boo boo, wipe all the sleepy, little eyes and I get to do this every day. I'm the one who teaches them what they learn and it's my values they are being molded by. I find security in this and I add this to my many blessings that the Lord has given me.
Am I tired? Oh you bet!! But I am happy and content. So, so happy!! Even if I'm slowly going crazy! ;)