What is going on??? Help!

Momof2girls👩‍❤️‍💋‍👩

Ok so, I’m 34 years old and had my tubes tied 11 years ago after my last child. I’ve had a period since I was in the 4th grade and they were never late, never irregular, nothing! Obviously when I got pregnant with my 2 kids I stopped having one but now I’m 15 days late day 44 of my cycle. What the hell could be going on? I’m so confused. I’ve taken several tests which I think are negative so idk what’s going on with my body. Could I be pregnant? Change of life? Any advice would be great. I do believe I ovulated later than normal but I thought I would’ve started by now. I’ve had some light cramping off and on this whole week but no blood or anything. Help please