TTC for 1 year and 3 months

My period was always normal n last about 7 days as i got older n had my son (now 5 years old) my period has gotton sooo light sometimes it last me 5 days sometimes 6 . Although is a normal cycle n i get it every month. Is very light n its almost just spotting . Can that be a reason why i havent gotton pregant!? Being that my period is only spotting. Iv heard that as long as you have your period you can concive. Maybe my period isnt normal. ?? ANY THOUGHTS??