My answer to your query is:
1.every Hair has to go through a hair cycle which consists of 3 phases that is Anagen (growing phase ) lasts for 3 years,catagen (resting phase ) lasts for 3 weeks,Telogen (falling phase) lasts for 3 months in which hair prepares itself to falling and new hair replaces it.
2.In some conditions such as fever,change of water,fibroid,hormonal variations in the body,post pregnancy,
thyroid problem,PCOD,fibroid and in severe stress most of the growing phase (Angaen) hair is pushed into the telogen phase and for which after 3 months there will be heavy hair fall suddenly so generally cause for hair fall generally arises 3 months back of actual hair fall when it appears.
3.So first answer that did you suffer from any of the above mentioned complaints 3 months back ? if yes then hair fall will subsides on its own no medication is required except the healthy hair diet.
Next Steps
first look into any of the medical conditions as i had mentioned suffered by you 3 months back
Health Tips
take a healthy hair diet consists of Protein (milk,almond,palak,flax seeds),12-13 glasses of water daily,de stressing activities and do not keep your hair wet and do not comb your hair when it is wet