Need advice

Can someone please help me? My son is 5 yrs old I have never been on birth control. Me and my husband has been trying on and off for the past 5 years to convince another baby. I've taken ovulation test and keeping track with my period and everything seems to be normal!!!! Only problem is after I ovulate I tend to cramp and spot a little bit and my boobs get really sore is there a cause for this? Can someone please give me some advice or tell me what's the best option for me to do?