From Longman Dictionary of Contemporary Englishhave second thoughtshave second thoughtsCHANGE YOUR MINDto start having doubts about a decision you have made You’re not having second thoughts, are you?have second thoughts about She’d had second thoughts about the whole project. → second
Examples from the Corpus
have second thoughts• But now, with the raft travelling more slowly than I had planned, I began to have second thoughts.• But then various men on the race committee and some male members of the National Aeronautic Association began to have second thoughts.• Somewhere between second helpings I began to have second thoughts.• Keep him laughing and he might have second thoughts about eating you!• Such incidents might have caused Sir Bernard to have second thoughts about the system; but he defends it with passion.• It was obvious that the company was having second thoughts about the whole project.• Perhaps Mr Harrison would have second thoughts if he walked in our neck of the woods.• I hope Darlington Transport have second thoughts on the matter.• Then, before she could have second thoughts, she picked up the telephone and dialled his number.• Couples contemplating divorce often have second thoughts when they realize how it will affect their children. 