Mixed Up Test Results? Is It Possible?

My boyfriend and I went in to be tested tonight. They did the Rapid test so we had our results within a 20 minute time period. There were two people ahead of us waiting and then a bunch of people came in after us.

When we walked in, we were given paperwork to fill out. We chose to do the test anonymously so we filled them out as "Jane Doe" and "John Doe" respectively. The papers had a number stuck onto to them so that when we gave them to the woman taking our blood, she could take the same number out of the file and put it on the vile that our blood sample goes into.

I went before my boyfriend and they pricked my finger and she put the sample into the vile. Then I was sent back out to wait. After I was done, my boyfriend went in and did the same thing. Then I was taken into another room and was asked questions. After I came out, my boyfriend was called in to do the same thing, but with a different person asking him questions.

During this time, one older woman that was ahead of me was taken in and given her results. (I mentioned two people were ahead of my boyfriend and I...the younger woman was given her results before I was ever taken in to get my blood taken.) After the older woman left with her results, I was called in to be given mine. The man said it was negative, and that was it. By the time I got out, my boyfriend was also out of his consultation and had been given negative results as well.

(I know this is confusing as hell. Try to bear with me, if you can.)

My question is: Is there any way they could have mixed up my test results? Basically, I'm worried I'm actually HIV positive but my test was mixed up with someone else's who was negative. So I'm walking around thinking I'm fine, but I'm not. I know it's rare but it IS possible.

My boyfriend says this is virtually impossible, as I was carrying my file with my numbers on it the whole time. The only time it was taken out of my possession was when the woman put it on the vile for my blood to go into. But I'm an extremely obsessive person (obviously!) so I can't stop worrying. He also says the chance of them mixing up BOTH of our tests would be even less likely. We have been exclusive for a year now so basically if I have it, so does he.

I wouldn't be so obsessive except I didn't leave my real name or phone number, so if a problem did occur, there would be no way to contact me. I'm thinking of calling them tomorrow to give them my number, just so I can feel better. But since I didn't give out any real information I feel like it would be hard for them to locate my file in the first place.

Ok, I know I sound crazy. Any words of advice? Do you think this is super unlikely?