What Is The Treatment For Tiredness , Spotting , Low Back Pain And Headaches?

Spotting,extreamly lethargic, lower back pain and headaches. we are trying for a baby for 7 months. i have had these symptoms before the last 3 periods it is not normal for me. i get the spotting from 4 to 6 days and then a period. i'm 24, weight 57kg, 165cm. we have 2 boys that were concieved within a few months of trying with both boys. only get these symptoms when spotting occurs i spend this time in bed as dont have the energy to get up. need some answers please