Opinions please

I got a positive on the 22nd and it has gotten a little darker but I’m not seeing a huge progression. I’m only so paranoid because I had a chemical at the beginning of January. I am 4w 1d and I haven’t had any spotting and very little cramping. The Dr says the line doesn’t matter and that I can come in for beta testing but it’s pretty expensive each time. I always said I wouldn’t do this. 🙈🙈🙈. I’m just super nervous. If the line doesn’t get any darker could that mean something is wrong?? I know your not doctors. I’m just asking by experience. The top is 2/22 all the way down to this morning which is 2/26. I also want to add that my hcg usually seems darker in the afternoon.