If tears well up because of one’s devotion towards Perumal, it is considered a form of offering based on bhakti. ‘svara nEtrAnga vikriyA’. Struggling to recite while tears run down during a stotra recitation is due to Bhagavad bhakti. These are not offences and there is no need to fear this and stop recitation. It will please Perumal to continue the devotion with such a devotional attitude. Svami Desikan says “bibhrato bhASpabindhUn”.