You thought it was safe because you were able to buy it in a store? You can buy cigarettes and alcohol in a store and we all Know how good those are for you! So that's a pore excuse to put something (potentially harmful) in to your body without any Knowledge of what it is or it's actions.
I answered this exact same question yesterday from another poster who had no idea what pct was and had just finished a cycle of tren. I'm amazed at how many people will buy something and ingest it without any knowledge of what the fcuk they are doing at all(so your not alone).
It is because of people like this that many of these compounds have been banned in the past and are under such scrutiny today. So I have to ripp your @ss a little for that!! And I would have to guess that's why no one has answered your post after like 60 views. However I do not think you have done any permanent damage to yourself (hopefully) after 15 days of use.
Yes you do need something for pct and since I doubt you have any idea what a SERM is or how to attain one, I would recomend you look into something like PCS from AI as I have read many good reviews on it. And providing you are at least 20-something and healthy, which it sounds like you at least want to be I wouldn't loose to much sleep over this. Get the pcs and I think you sould be alright. We all make mistakes (I'm no fcukin angel myself) so lesson learned. Good luck to you dude....