Baby Shower Anxiety

My best friend and sister in law are throwing my baby shower next month (early May).
They originally told me it was May 7th but then accidentally let it slip it's really on the 1st lol
Background: I'm VERY type A and take being called a control freak as a compliment lol they are both very good with organization - but AWFUL with keeping secrets. The fact they've kept anything a secret thus far is a miracle and shows how truly hard they're working to keep things a surprise.
So, to show them how appreciative I am I've quelled my controlling nature and have worked my butt off to NOT involve myself and be nosy lol it doesn't sound like much, but it really is. 
So this past weekend my Mother and MIL have accidentally spilled that the location of my shower is AT MY HOUSE! 
I swear I didn't ask, they completely forgot it was a surprise until I looked shocked lol
Anyways, I have NOT told my friends I know the location because again, they're so proud they've kept the secret and I don't want to ruin that for them.
But now my anxiety is 100%.
If it's at my house... I don't have room for 15 people let alone 30-40!
If it's at my house I'll need to know to make sure everything is clean and picked up... I don't have enough seats!! Plus one of my husbands aunts is handicapped and I have no ramps! Only stairs!!
Maybe it's in my backyard? Except I have dogs! So we'll need to de-poop the yard!
No need for advice I suppose - just needed a moment to freak out! I dont know what to do if it is at my house which I'm 99.9% positive it is. 
Gah!!!