First of all, a Protestant isn't asking the Catholic God (the only God, that is) to bless you. A Protestant is 'praying' to whatever 'god' they've manufactured in the last 100 years or so.
Ergo, Protestant 'blessings' are nothing more than nice sentimental statements. Meant well, they are harmless. If included with the 'blessing' is some sort of hint or mention that you 'walk with j-zus' (NOT Our Lord Jesus Christ, hence the misspelling) or that you 'draw close to gawd', then be careful. That person might realize you're a Catholic and they might be 'praying' that you be converted to their heresies.
Secondly, it surprises me how many people simply don't catch the tricky little clause in the definition of validity as it relates to schismatic or heretical sects performing acts like baptism.
The definition of validity includes RIGHT INTENTION, that is, an intention to DO WHAT THE CHURCH INTENDS TO DO in administering said baptism.
PERHAPS an Anglican or even a Lutheran, who believe in baptismal regeneration (that is, being born again through baptism, having one's original sin and any actual sins remitted THROUGH the sacramental grace of baptism) might have the correct intent.
An 'evangelical' Protestant, or, for that matter, the vast majority of so-called Protestant 'christians' in the world, would NEVER have the right intent if they were faithful to their (heretical) theology, because they would never baptize someone with the INTENT of remitting sin and actualizing entrance into the Kingdom of God and into sanctifying grace.
Do yourselves the favor of staying away from as many occasions of 'ministerial' contact with Protestants and other heretics as you possibly can. Keep away from 'National Day of Prayer' events, Prot-sponsored tables at fairs, etc and you'll avoid most of the most committed 'believers' who would want to 'bless' you.
Immaculate Heart of Mary, triumph soon!
Most Sacred Heart of Jesus, have mercy on us.