No, all damage is dealt simultaneously.
- Combat Damage Step
510.1. First, the active player announces how each attacking creature assigns its combat damage, then the defending player announces how each blocking creature assigns its combat damage.
510.2. Second, all combat damage that's been assigned is dealt simultaneously. This turn-based action doesn't use the stack. No player has the chance to cast spells or activate abilities between the time combat damage is assigned and the time it's dealt.
You would need find a way to give Bellowing Aegisaur first strike or double strike to do what you want.