Hey Everyone!

I have a quick question that has been bothering me for the last few days so I thought I would ask it here since I can't seem to find the answer anywhere else.

So I'm aware of the different hair cycles (correct me if I'm wrong) and why this causes healthy hair to shed. Most websites explain that your Anagen phase (the growing phase) usually lasts on average 3-5 years, then the Catagen phase, and then finally the Telogen phase which is when your hair is released and falls out of your head. My question is: 

If I lost all my hair, and it just now grew back and has only been on my head for around 6 months, how can any hair I see fall out of my head be considered "normal shedding"? I always reminded myself that the few hairs I find in the shower and on the pillow are just normal shedding but, how could my hair have possibly gone through all three phases if it just grew back a few months ago? What is causing the hair shed and IS this totally normal?

Thanks in advance guys! I really appreciate this community.