Regular But Painful Periods Sometimes With Very Less Flow And Foul Smell

I m 25years old,virgin,my periods are painful but are regular. Previous month after 15 days of my periods ,a red discharge occoured through my vagina which didn't last even for a day,it was very little but has a very foul smell. i neglected it but this month agan the same thing happened,my periods ended on 5th dec n yesterday red discharge occoured,this time the quantity is little more,i doesn't feel any pain during its flow.i m very much worried about it.is there any problem regarding it? can it cause me infertility in future? also tell me about red lukoria.