Pregnant or not pregnant??

Hi everyone! 😁 please no judgement! I would like some advice!

So, I hooked up with someone on Thursday, April 11th; and on Friday April 12th I took a Plan B pill because he came inside me! Well after taking the pill and telling him, he tells me that he had a vasectomy years ago. I just got off of my period, May 1st-May 6th and it was a little early but I figured it was because of the pill. Well ever since I’ve been off my period my stomach has been crampy so just to be sure, I took a pregnancy test this morning!

At first the test was reading negative, so I took the test with me to work to look at later. The test sat in my car from 10 am to 4 pm in about 75 degree weather and it said positive when I looked! So I went to buy another test and I just took it about 20 minutes ago;it’s reading negative.

So ladies, am I just bugging out? Or am I pregnant? Help please!