OCD/ anxiety panic attacks.

My story is some what complex and I probably sound nuts so I'm sorry bare with me. 
I had my son 18 months ago! I know a long time but I still like I have ppd. Is it possible to still have these symptoms so long after?! 
All I do is clean and wash laundry all day. Now that my sons runs and climbs on everything it drives me crazy. Not him of course he's perfect. It's the anxiety!!!
I live in an oldhouse; and like all old houses, we have some unwanted visiting pests here and there. My new obsession is checking the house over and over again for mouse droppings. I won't let my son go near the radiators or the baseboards or even certain places outside I feel like mouses could have walked. 
This is all because I read how dangerous it is to touch and breathein mouse dropping particles. 
So naturally with the baby that touches everything, my OCD has sky rocketed. 
I can't stop obsessing over it. I feel like it's ruining my life. 
If I find a couple mouse droppings somewhere i literally have a panic attack and start crying and sweating. It's so crippling and then I have to clean. 
What can I do? Any mothers have any experiences that are similarly or any advice?