Is it normal that after taking Belara tablets the jaw on the left side hurts very much?

One-sided jaw pain is not a typical side effect of Belara tablets. Such a side effect is not described for this medicine, and although some very rare side effects may not be covered in the documentation of the medicine, the cause of the pain should be sought elsewhere in the first place. It seems that it may be helpful to visit your family doctor, who will guide you further. I enclose additional information about Belara - prescription products can be booked at WherePoLek and collected stationary upon presentation of a prescription: https://www.gdziepolek.pl/produkty/9841/belara-tabletki-powlekane/apteki/w-warszawie