What looks like a moving star that moves in a straight line but behaves a jerky movement?

I just came from balcony, watched the stars as it is completely clear night outside. I saw what looked like a normal star but it moved from north to south in a straight line. I started observing it when it was directly above my head. There was no strobes and no sound, it was moving also quite fast. I thought that it could be a satellite but then as I observed it I noticed its jerky movement as it was constantly speeding up and slowing down in two second increments. After a minute I called my girlfriend who was inside to come and look. We observed it for about three minutes, as it got farther away it got dimmer and eventually we went inside.

Satellites, airplanes speeds are constant. This was not.

Does anyone know what it reasonably might have been?

Sighting was in Estonia, Tartu, 26.04.24 23:00.