Clogged milk duct?

Hey all, I'm 30 weeks and 5 days and have not experienced any leaking of colostrum so far. Last night I noticed a stinging pain on my nipple that had a little bump. This morning, it is still there, and stinging and aching more. From what I'm reading, most moms can express it to make it feel better, but because I've not produced anything yet, I'm not sure that's an option. Any ideas? Or could this be something entirely different?

My concern is having one and not being able to nurse when baby comes if it continues. First time mom here. :)