I think my breaststroke is OK - I regularly swim ~25 lengths and my head goes under the water after each stroke. But, I often feel like I'm at an angle in the water from head / up to feet / down. Sometimes I get a sore back as I feel like I'm arching my back or something. I also don't seem to be going very fast for my effort - I watch other people, and they seem to make efficient progress with slightly random swimming styles, whereas I seem to make slow progress with what I think is reasonable arm and leg swimming style 😄.
Are there any resources I could look at to try to improve things? Do I just need to try a bit harder to go faster? I'm trying to work up to booking a few lessons as well.