Did Gandalf ever doubted his decision of taking Bilbo with him?

 It is not explicitly stated in J.R.R. Tolkien's "The Hobbit" that Gandalf ever doubted his decision to take Bilbo Baggins with him on his quest to reclaim the Lonely Mountain from the dragon Smaug. However, Gandalf does express some concerns about Bilbo's ability to handle the challenges that lay ahead, and he is initially skeptical of Bilbo's suitability for the role of burglar in the quest.

Gandalf ultimately chooses Bilbo for the quest because he sees something special in the hobbit, and he believes that Bilbo has the potential to rise to the occasion and become a hero. Throughout the course of the journey, Gandalf acts as a mentor and guide for Bilbo, helping him to overcome his fears and doubts and grow in confidence and strength.

In the end, Bilbo proves to be a valuable member of the company, and his bravery and resourcefulness help the group to succeed in their mission. Gandalf's faith in Bilbo is ultimately vindicated, and the hobbit becomes a respected member of the community and a hero in his own right.