Small oil leakage

Hello everyone, I am new here and I wanted to tell you something to see if you can help me.
I have a Seat Cordoba 1.4 Gasoline of 99,
a few days ago it takes it to the mechanic of a lifetime for a noise in the engine that turned out to be the taques,
it costs me € 250 The joke with the change of oil and filter included.
I have always put the one who brought from the house on 20/50 but the mechanic this time I recommend putting 10/40,
the case is that I took it out of there and it was soft like silk, but pulling oil (something that did not do)
it takes it to the mechanic,
he says that he has not touched anything down there, yet he has changed me a retain, and he no longer throws oil in that exaggerated way, I
still observed that I have observed that every time I have observed that I have observed that I have a Tiny oil droplet on the ground.
What do I do? What can it be?
Thanks in advance

First, first, clean you will see where it tries to start that to start and then we see what to do when we know where it comes from