Pregnant!?

My husband and I tried for 3 years to get pregnant. Finally, we did 3 rounds of IVF, and finally got our little boy. He’s almost a year and a half and we were planning on doing another cycle right after he turned 2 but I’ve been feeling really odd and told Josh that I was sure I was pregnant even though I couldn’t be. But we’re packing up our house to move and I came across some HPTs from back in our ‘hopeful, what-if’ days. So for shits and giggles, I peed on a digital. Blazing ‘pregnant’. Then.... after freaking out. We decided it must be expired. So I peed on a line test so we could see how dark the line was. After chugging a bunch of water and 30 minutes later.... still positive!!! I’m in shock and not really processing. Our doctors said we had a better chance of winning the lottery!