Back to school

My son went back to school today, first day in 1st grade. He's so big, I can't believe my baby is in 1st grade already! I had to walk him in to school today to help him with his box of suplies and to meet his teacher. I was terrified that someone would stop and ask me something about the baby (I lost her the a day before school was out). My DH went with me for support. He said he would answer any questions for me. Luckily I was able to get in and out without any questions.
We had planned his return back to school thinking that I would be off by now to have the baby since my due date was 8/27. I was very sad today thinking that i never saw this coming . I miss the person I was then, innocent and happy compared to now.
To add to my anxiety I am ttc and AF is due no other than 8/27. I have PMDD, which makes me 20 times more emotional than most women with PMS; I was so depressed last two periods that I called off work and didn't get out of bed. I'm praying that I will make it through in one piece.  I can't call off work because we're already shorthanded that day, so I'll have up my meds I guess.  I know I can do this, please God help me through!