It was normal to be uncertain whether the girl really liked or loved him because love was complicated and uncertain. However, if he felt that his feelings for her were just a momentary impulse or that he did not know her well enough, he might need to consider whether he should continue to pursue her. Love required both parties to work hard and make a mutual commitment, not one-sided persistence. If you're not sure if she feels the same way about you, it's best to talk to her honestly and ask her how she feels about you. This would help him understand her thoughts and feelings and determine whether he should continue to pursue her. If she doesn't feel the same way about you, then you need to respect her decision and don't give her any negative emotions or pressure. Instead, he could try to let go of his feelings and look for new opportunities and people. Although love is not easy, sometimes you need to look forward to better meet the challenges of the future.