Could it be?

My Cycles are usually irregular, so it was hard to actually put down estimate times of the past month but I tried. My last cycle ended on New Years. However I started about 3 days ago ( I think) and it doesn’t look normal. Even with being irregular my cycles are heavy and regular consistency for about 5 or more days. 3 days ago it’s been all a darker color and only spots. Today it mostly stopped but I woke up with a huge headache; which I never get and nausea all day long and not wanting to eat much. Could this possibly be implantation even though the conception time seems off and was during a low percentage of ovulation. I also get cysts on my ovaries every now and then and have a pending diagnoses of possible Lyme disease. I’m not sure if it could be related to pregnancy or my existing issues.