You can see the number of your remaining gifts in the mall (gift shop) or when you give a gift to a girl. (check the number at the top left of the gift icon)
For the drugs, the bartender at the disco will show your drugs inventory (after entering the password) or when you organize a party at the night club.
You can see your amount of remaining "bonus" condoms when you purchase new rubbers at the pharamcay or by using one.
I didn't get a sextoy during a fuck off. But in the sexshop, you can only buy one of each sextoy. I imagine then, your collected toy is lost if you already bought it.