Hi again ready - yep just offer the one boob, by all means if she comes off, wind her (although she should not need it) and then offer her same boob. If she takes it, then great, if not then don't worry, she has had enough. If you keep going with switching boobs she will become accustomed to the foremilk which is sweeter and taster and will start looking for that more, it is like offering a child a sweet drink before a meal time, they can fill up on the drink and then not want so much food. So do just stick to one side each feed session, but if H is coming off to look around and being distracted, offer her the same boob again when she is ready.
Up to about 6 weeks then babies do need to be fed every three to four hours, but after that then you can start gradually adjusting feeds, so that they move to more "meal-time" feeds, so during the day: breakfast, lunch, teatime, and before bed, and then a nighttime feed. The night-time feed can be dropped by around 4 months, but some babies don't like going that long, so nearer to 6 months. However, some babies are snack-y babies, they like to graze feed rather than having big gaps. Their bodies are capable of going longer, but they like the comfort of the snacking (and having the sweeter foremilk!). That is great if it suits mum and baby, but otherwise you can start to go longer between feeds. Some babies also revert to wanting snacking when teething, as the sucking action soothes the sore gums. Also next thing is that around this time, you will stop feeling "full" with your breasts, as your supply is now matching H's. So don't be thinking how full/empty your boobs are, it is not a helpful guide now. You will feel more full if you have had a longer gap between feeds than normal, but your body will now have adjusted to H's needs.
Try to forget what the HV said, just know you were doing the right things and H's weight is ok, even if she put on nothing this week, with being alert and having wet nappies is a very very good sign she is thriving on your milk. As for dirty nappies, breastfed babies can go for upto 3 days without poo-ing and this is normal.... because the milk is matched to their needs, there is less excess to excrete. But you do need to be sure that their are wet nappies each day. A breastfed baby with dry nappies during the day is a dehydrated baby with not getting enough food. But this does not sound like your H. Sounds like she is doing great. You are doing well Ready, just keep up the good work.