Mina's head was pounding, and not just because of Connor's proposal, the loud music, or the people staring at her. Mina was angry with Willow for having invited Connor to Wayvair, because she was afraid that the man's current infatuation with her would not fade in time, and he would pull some grand romantic gesture at the event.
Willow assured Mina that Connor went through intense phases since he was a teen, and she saw his declaration as nothing more than that, but she did admit to not expecting his reaction. From what Willow remembered and from what Olivia confirmed, Connor had not received presents for his birthday ever in life.