I am in breast feeding! my baby is 4 months and 1week. today i have lose blood, it seems like a period cos it a little bit cramping!is it a period ?

Period?: It certainly is possible. Remember to use birth control as you are likely fertile again.

Sounds like a period: Even with breast feeding, it is not uncommon to start cycle again around 4-6 months post-partum. If no other symptoms and seems similar to periods you had before you became pregnant, i would assume you have restarted ovulation and thus your monthly cycle/periods.