Normal or no?

My daughter is 3 and potty trained except for night time and she only wets occasionally. She has still been using her little potty we started her on because that’s what she felt comfortable with and I didn’t want to force her to use the regular toilet until she was ready. My mil watches her during the day and says that she will go pee constantly and sometimes have accidents. This all started when she started using the regular toilet. Could it be that she’s not fully emptying her bladder the first time she goes due to sitting at a different height? She doesn’t complain of any kind of pain and there hasn’t been any blood in her urine either