What Could Be The Red Spherical Things In Blood During Periods?

hi, am 26 years old married and i weigh 52kg.During my period two days ago i noticed tiny red perfectly spherical things in my blood that were about the size of a half millimetre.they were there throughout the whole period, am so worried what could this be? Before i have been diagonized with severe gastritis, flattened villi, have a spoilt valve and my digetive system is irritated with anything with preservertives or processed foods causing abdominal pain and flatulence.