The Roman Missal, Appendix II:
RITE FOR THE BLESSING AND SPRINKLING OF WATER
- On Sundays, especially in Easter Time, the blessing and sprinkling of water as a memorial of Baptism may take place from time to time in all churches and chapels, even in Masses anticipated on Saturday evenings. If this rite is celebrated during Mass, it takes the place of the usual Penitential Act at the beginning of Mass…
- When he returns to his chair and the singing is over, the Priest stands facing the people and, with hands joined, says:
May almighty God cleanse us of our sins,
and through the celebration of this Eucharist
make us worthy to share at the table of his
- Then, when it is prescribed, the hymn Gloria in excelsis (Glory to God in the highest) is sung or said.
The sprinkling rite takes the place of the penitential rite which takes place before the Gloria. The rite of sprinkling clearly states that the Gloria is *after * the sprinkling rite.
You can ask the priest why he does it that way or raise the issue with a member of your parish council (if there is one). But while combining the sprinkling rite with the Gloria is illicit it doesn’t rise to the level of abuse that would affect the validity of the Mass.