Don't mean to offend here, but didn't you notice a spider on your neck? Did it bite you while you were sleeping?
We have these things, or a relative, here in Michigan. I spend much time outdoors and I've never been bitten, though I know of one person who has (a surveyor).
The territory I live in is lousy with mosquitos; I always leave spiders (and bats) alone for this reason.
Both times I was bit. I never saw the spider or felt it. I only felt it after it became inflamed and grew larger. Again I live in the country... they are everywhere! We have a thick wooded are right behind the house and corn fields all around us. Pets can also be bitten, they have some pet case on the website link I posted above. I see hundreds of them every year some in my house at times and other outside. As soon as you clear them out more move back in the house or around your home. I have many gardens on my 5 acres of land also. You can keep your dwelling spotless and still get them inside your home they are small spiders that do not normally come out in the open. You usually find them hiding or right after you have sprayed.