BFP but low HCG?

I had my blood taken this morning, exactly two weeks after my 2nd round of <a href="https://glowing.com/glow-fertility-program">IUI</a>, and it came back positive !!

We are so thrilled as we’ve been trying for quite some time but I’m a little nervous. My HCG was 22 which the doctor advised was low so I’m going back Thursday for another test and they are hoping the number has doubled. I am now experiencing some light cramps / lower back aches and I’m freaking out that this isn’t gonna stick...

Anyone have a similar experience?