Dig your finger into the topsoil, down to your first knuckle. If you don't feel moisture down there, it's ready to water. Lift the container and get a feel for how heavy it is. When you develop a sense for what is "too light" you'll be able to check containers more easily.
Watering once per week sounds too infrequent. But, the more important thing is to have good wet/dry cycles. If it takes a week, then that's what you need to do. In future grows you may want to add 20-40% perlite and see if you can get it down to every 2-4 days. I do every 2 days with Peat moss and Perlite. If I add 20% potting soil, it's closer to 3 days which I like a little better using more organic nutrients. 2 days was good when using purely synthetic nutrients.
As a newbie you want to be careful of your soil ph. I think that's the biggest problem for newbies. Did you add dolomite lime to your soil before planting? That helps hold the ph steady and adds ca/mg which the plant needs in early- to mid-flower. You'll probably have a deficiency at that time. If I were you, I'd measure runoff ph and TDS ppm. Keep in mind how long the water rests in the soil before being displaced into runoff (and how much runoff, it's better to have just enough to measure. If a lot flows through, it mixes with water that might have sat in the container 10 minutes, throwing off the time variable you want to keep track of). Runoff ph isn't accurate. But, it can help you assess what's happening when a problem occurs. If you see runoff drop from 5.8 to 5.2 over a few waterings and you start having a deficiency, you'll have an advantage when choosing how to respond. After you have a soil/nute combo worked out, you don't need to do this.
Looks good, especially for a first grow.
