Basking Question

Hello All, I’m new here and I recently became a proud concentic dbt pappa! 🙂 I’m not entirely sure of the subsepecies yet, but I think she (also not sure of the sex yet) is a Northern. She’s got a carapace of about 2.5″ to 3″ I would say, and I believe she is about 4-5 months old if the breeder I got her from remembered correctly. She’s in a 10g tank at the moment, but she will be moved to a bigger tank in a short time. Her water is at 78 degrees, give or take. I do have large aquarium gravel in the tank, but I will be switching to larger river rocks or filter sand when I put her in the bigger tank. I check her poop to see if any gravel come out and so far nothing. I have seen her nibble on some of the gravel a couple of times but she spits them right back out. She is a digger though. Anyway, my main concern is that she hasn’t been basking yet. It’s been a week but she doesn’t bask. She goes on the basking dock to retrieve her cuttlebone now and again, but she doesnt normally stay up there. I have a 50 Watt UVA/visible bulb in about 8-12″ away from the dock. I had it at about 6″ away but the reptile lady at petsmart it might be too hot for her since she’s still little. I am also in the market for a goob UVB lamp/bulb, so don’t worry. In the meantime, I bought a repcal calcium/vitamin d3 supplement that I sprinkle on her food a couple times per week. She is very inquisitive and lively and I find myself just sitting there watching her swim. Well if you are still here and managed to get through my winded post (sorry), I wanted to see if anyone had any advice. Is this normal? I know she’s still getting used to her tank, and maybe im just a worrywart. Thank you ahead of time for any/all advice. Miguel