My daughter started solids at 6 months (2 months ago) and she is hard to read when she's had enough or wants more - pretty much the same reaction, otherwise I would go by her cues. I'm just not sure if I'm feeding her too much or not since she doesn't really let me know if it's too much, she will just keep opening her mouth for the spoon.
I always breastfeed first as well as random times throughout the day - so most of her nutritional needs are met that way. I'm not interested in weaning yet, I just want to be sure I'm not overdoing the solids.
Typically, we will do fruit and oatmeal for breakfast - fruit and vegetable for lunch and fruit, vegetable and oatmeal for dinner. The quantity varies, but it's often around 1/4 cup to 1/2 cup each time.
She's good with self-feeding too, but again, she just doesn't seem to have a *stop, I'm full now* switch, so the quantity of that is in question too.