Hi and thanks for the post

It's not unusual for some people to have what's called 'glandular' or 'lumpy' breasts - The breasts are made up of glandular and fatty tissue and people in their 20s and 30s tend to have dense breast  tissue -  this can tend to feel lumpy compared with more fatty tissue.

This is why mammograms are not done in people under the age of 40 , as it's more difficult interpreting results due to very dense breasts. Ultrasounds would usually be done instead if needed.

Breast cancer is uncommon in someone of your age , though I can appreciate that it's difficult not knowing what may be causing your symptoms. Hormonal changes can cause tender, painful breasts and there is some information about that here  

Keep an eye on things and do go back to the GP if you notice any other changes you are unsure of .It's hard waiting for an appointment , you can try asking to be put on a waiting list if there is a cancellation, or although costly, you can ask to be referred privately.

I hope you don't have to wait too long

All the best

Wanda