I finally could solve the problem and it as nothing to do if its diferent piezo or not(tried with two). the values you're getting, in this case 1023 as to do with voltage going through piezo and going to analog pin(because obviously) the piezo is getting 5v from supply. So, after some research i found other way to connect piezo to circuit,like in picture below and i started to have normal readings. At first i was thinking that we would cause some resistance vibrating piezo, causing voltage divider and get a reading but we would need to create big resistance on piezo to get readings from 10 to 100 and i thought that is weird.But now, (although i dont get any votage read from multimeter),from what i understood we cause some voltage vibrating piezo and thats the voltage we read,because my values are around 15 i dont get that reading on multimeter anyway i think its how it works. cumps
votlage=(15/1024)*5= 0.07v
