I agree with Ford Girl. You need to be very consistent otherwise you will indeed confuse your pup. He needs to know you're pack leader.
I remember it taking awhile for my pup to be trained.
We signed him up Mid or end of August and we were still taking him to classes in December (if I remember correctly).
Our classes were once to twice a week. We had our classes outside so depending on the weather (rain) our class would get cancelled. Also we had him fixed during that time so we missed some classes.
Also, I remember my trainer saying that pup's have a small attention span SO to train them for short periods of time otherwise they become frustrated and you won't get anywhere.
He did mention that YOU NEED to always practice!!
I remember taking 30 mins and work on only 1 exercise that's it. Then I would practice later on in the day but never for large stretches. And, always leave off on a happy note.
It's been awhile back but that's what I remember. Boy talking about this brings back all the moments I had with my pup.
It's hard I know BUT believe me and the others when we say it will get better. At some points I thought I wanted to quit because I thought we weren't getting anywhere. Now I have a good boy and you will too!!
Hope this helps.
The more people I meet the more I like my dog.