I have been using the Blockfolio app for Android, a portfolio app where you can see all your coins, holdings etc.
But most coins I have bought them with fiat money, so I do not know what the initial price in bitcoin/satoshi is worth.
The app only lets you enter satoshi amount. If you enter your amount in USD or EUR, you have about 1million growth or loss

For example:
I bought 7500x Dogecoin for a total amount of 11,05 EUR. That means 1 Dogecoin is 0,0014733 EUR.
I bought 10000 x Reddcoin for a total amount of 18,81 EUR. Theat means 1 Reddcoin is 0,0018810 EUR.

How exactly can I know what the initial price is in satoshi? How much is 1 Dogecoin (0,0014733 EUR) in satoshi? And will this conversion be accurate?
I have all my coins in a selfmade Excel file but yeah, it doesn't show my increase or decrease percentage