My Mom Is 81 She Had 3 Parathyroid Removed 1

My mom is 81 she had 3 parathyroid removed 1 month ago. After surgery he told her to take 2 tums a day. She has been admitted in hospital 3 times since surgery. She is on no medication now. The hospital said one time her sodium was to low. The other 2 times everything was perfect. Her symptoms are. Weak, anxiety, very cold all the time. All she says is I don't feel right. Please advice.