Anxiety

Hello,

About 2 months ago, my wife and I discovered we had mice in our house. Since then I have been a nervous wreck.
I had called an exterminator and he did his thing by setting up bait traps around the house. He told us that our infestation was very minor and not a worry at all. Those words comforted me for about 3 minutes.
It is not the mice that I am afraid of. It has more to do with the fact that they were there in the first place.
The exterminator told us that it would take 3 weeks to get rid of the infestation. It has been 5 weeks since he was at our house. I was becoming comfortable again when there was no sign of the mice. That was until last Saturday when I saw something I wish I hadn't.
I had to shut the water to my backyard to blow out the sprinkler system for the winter. The knob to turn off the water is hidden in the ceiling of my basement. I removed a tile and climbed up to turn the knob when I saw the mouse droppings and chunks missing from the poison the exterminator left up there. At first I thought that the exterminator had done his job and all was fine. Then the anxiety hit.
I cleaned up the area with the droppings and put the tile back. Whoever I have a constant compulsion to check the area to make sure no more activity is going on. It is almost a week and there has been no more activity. I am more then sure that my home is more then likely mouse free but the feelings persist and I am constantly on guard in my home, never just relaxed and comfortable. I have trouble eating and don't like leaving the house empty.
It is affecting my work as I can't concentrate on anything else and I know my health is being affected as well.
I am hoping that writing about this will help ease my worries. I know that I am making major mountains out of molehills when it comes to the mouse situation but I can't help it.
I am hoping time will heal but have vowed to seek help if this feeling persists. I am usually very friendly and outgoing. Now I sit around doing nothing. Always worrying about what will (supposedly)happen if I am not around to prevent it.
I feel like such a loser that something regarded as minor is driving me to a point where I just can't function.
Any thoughts or words of advise would truly help.

Thank you.