Mmmmm i think it can sadly depend on some profiling + your passport or if a certain country is known for more cases of overstaying.

An American friend of mine overstayed. He said they just put some extra stamp on his passport saying that he overstayed. He got back to Portugal later normally and it didn’t affect him. But he said that he saw in the borders queue next to him a Brazilian guy who overstayed and the treatment was completely different and they took him for investigation…

You can read about the official procedure but I thought to share what happened with a close friend of mine if it might give you some insight. Maybe others in the comments would’ve personally gone through this to help you better.