It has been 4 mos. since i gave birth and i am now suffering from memory loss. is it normal?

Depends: The extent and type of memory issues can vary widely ranging from normal to a sign of a disorder. You'd need to be carefully evaluated in steps from a screening thru imaging if results merit such a process. Calmly collect a week or two's detailed descriptions of such events noting time of day, duration and storyline - like a reporter would. See your Dr. w/ this report - be examined. Best wishes!

Not uncommon: There is the reported phenomenon "mommy brain" or "baby brain" during which there is reported memory disturbances. The research isn't great but there is some data to suggest that it does really exist. The literature suggest it can last up to a year or so post-partum. But I would encourage you to seek the help of your primary care to make sure a mood disorder isn't contributing too.

Get evaluation: Whether you have the mommy/baby brain that Dr. Southard describes or there's a mood disturbance as Dr. Weixel mentions could be also possible the first step is to have a functional evaluation of your metabolic and endocrinological status to see if other addressable causes are present. Generally, the condition resolves in due course. A sign that your "fog" is benign is how well your baby's growing.