Need some help

I am 35 years old. My husband is 41 and we have 2 beautiful girls. After my birth in aug 2017 I got my tubes tied. Then in November had a scare of pregnancy but the blood test came back neg. fast forward to Jan. I was three days late for my period but I then got it. But I tested anyway and a positive came up. When I ended it I took another test and two lines came up but darker. I have a appt for feb 13 because my mom said w the hot flashes I was going through pre menopause. Has anyone else had their tubes tied and been pregnant? Or could pre menopause cause a hpt test to darken. Thank you.

UPDATE::

My blood test came back at 0.12 so that is as negative comes. And I had another test darker this morning. It didn’t do anything from Monday to Wednesday. It maybe Perimenopause. Or some other issue. Which I have a drs appointment feb 13. Thank you all for ur input.