An increase in bite depth points to increased craniofacial dystrophy, whether it be downward growth, CW rotation or whatever. Please describe your technique in detail. Are your teeth together or apart? Touching or clenching? Is your tongue in a suction hold or a push hold? Are you applying more pressure with anterior or posterior tongue, or is the pressure equally distributed? Does your tongue touch your teeth? Do you chew gum? How is your lip seal?

@progress Thank you for responding!

In the beginning I may have clenched, jaws hurted sometimes but after short time it became more touching. But I have focused much on the bite: I heard that the molars should touch lightly so I focused on letting the molars touch. Before I began with mewing my molars did not touch when I closed my mouth, so in order to let them touch I had to adjust my bite a bit and it seems like now this has become my normal bite, with overbite as result.

I think the tongue is more a push hold and I think that another main problem could be that the tongue touched the teeth in the first month. And I think pressure have been balanced between anterior and posterior tongue but in the beginning it was hard to put pressure with the posterior part.

I have chewed gum much, big balls of gum many days. Lip seal was always normal, no pressure has been put on the lips.

Can you see from the pictures whether this is a big overbite? An abnormal overbite? I have never had this before..
Sometimes I read it is normal when you begin mewing but it feels so abnormal for me..

Posted by: @manoman97

But I have focused much on the bite: I heard that the molars should touch lightly so I focused on letting the molars touch. Before I began with mewing my molars did not touch when I closed my mouth, so in order to let them touch I had to adjust my bite a bit and it seems like now this has become my normal bite, with overbite as result.

This is likely to be the culprit. In one study it was found that masseter use correlated with downswing of the anterior palate. The masseters, unlike the temporalii, are not really postural muscles, just masticatory. Molar contact has to be performed by moving the mandible upward/backward towards the last maxillary molars, rather than upward/forward towards the incisors.  I've written about this here and here.

@progress Ok thanks! Some questions though...

My English is not very well (not native) and all the terms used in these articles are hard for me to understand.

1) Is the conclusion of the articles that my molars should not touch at all?
2) Will the slight overbite that I created be fixed by mewing properly?
3) I just woke up with my tongue vacuumed to the top of my mouth. So it seems like it starts to hold it automatically here. However, the tip of the tongue touches the teeth. Is this a problem?

Thanks in advance!

@progress And is the overbite that you see in the images a bad overbite? Too far?

1) touching is fine, possibly even desirable, so long as you are not clenching with the masseters.

2) in theory yes. Since you gave yourself overbite after a few weeks, chances are you'll be able to reverse it in similar amount of time too.

3) try to avoid touching the teeth with the tongue if possible

Posted by: @manoman97

And is the overbite that you see in the images a bad overbite? Too far?

Technically any overbite is "bad" overbite. However, your overbite is quite mild, so mild that most orthodontists would probably not be interested in treating it.

@progress Thank you so much!!

So my overbite will not get worse?
It is normal that the upper jaw moves forward, right..?

@progress And you say that it is fine if the molars touch, but when the molars touch, then I have overbite..

@progress and with clenching you mean giving pressure when the molars touch right?

Honestly, I don't notice anything wrong. If this worries you so much, contact your dentist, he will tell you