Odd period

Hi I have been TTC for about 4 months now, but since we have started trying, my periods have been extremely off. I will start with really really thick dark red or brown spotting for about 5-10 days and then go into a light to medium flow period followed by the thick spotting not again... Sometimes I will go 3 weeks total days of the spotting-period-spotting. Had anyone else had this issue? I just think that it's odd that it's happened only since we started trying.. Any suggestions, thoughts or questions welcome. Thank you! ❤️