Hi Alice,
I have ordered from ainterol.eu a few times. Delivery has taken typically 3-4 weeks.
The latest order I made was 13th April, and I paid it with PayPal. They sent an Order Confirmation the same day, and an mail informing about shipping on 18th. That latter mail had also tracking number. Please look again that mail, Mine had a tracking code in the mail, and also a big button to click to see the order status on their web site (which also offeres a tracking service), You may try to check where the parcel is just now with
https://parcelsapp.com/en/tracking using the number which should be on their mail.
Earlier deliveries from Ainterol have taken 3-4 weeks to Sweden. This time I can see that the packet, sent as a registered mail, has passed customs and should be soon arriving to a local mail pickup point (where I have to sign for reception). In other words, it might arrive this week.
You seem to live in Italy, and there are two national institutions interpreting the EU rules and local laws: Customs and the Postal service. They may have more handling time or even complications which I am not aware of. (Unconfirmed rumors say that they might be less efficient than Swedish ones, but who knows)
I hope you find your parcel with this information!
-Teddy