Irregular cycle TTC

My husband and I are only on our second month TTC, but I’m nervous. I’m 5’6 and 260 lbs and I’ve read getting pregnant can be hard when overweight but I’ve also read it’s not that big of a deal. Also, my periods are irregular, ranging between 28-35 days usually. This month I’ve been spotting off and on for a little over a week now but I’m not supposed to start my period until the end of the month. What does this mean? Should I be worried about not getting pregnant?