Au contraire, my champ-pattering friend. The solution here is to play the long game. Invite your mother along with you enthusiastically, treat her to a day out shopping, lunch, drinks and spoil her with gifts. Then, as she is thanking you for a wonderful day, look deeply into her eyes, clasp her liver-spotted hand in yours and huskily whisper to her that you are in love with her. Lean in and attempt to mouth kiss her. If she recoils, act like it was all a big joke and quickly change the subject. If she embraces the Oedipal sexual tension then ride her like a Blackpool donkey.
In the morning after your love making / awkward attempt to seduce your own mother, she will have forgotten all about knowing what Christmas gift you had bought her in advance.