Waiting for breast biopsy, out of my mind with worry

hi everyone, I noticed a lump on my right breast and went to breast clinic. I'm 33 so they did an ultrasound - they said there is a patchy lump about 3cm big and that 2 lymph nodes look swollen on the ultrasound (but not to touch).

I panicked and immediately assumed cancer and everyone else started talking like it's cancer too, saying stuff like 'we'll treat it' and that once the biopsy results come back I should be prepared that treatment will start quickly.

I'm in total panic mode, can't eat or sleep and feel sick constantly, I don't know how I'm going to get through until biopsy results.

I'd like to know, can they tell from an ultrasound whether it's cancer? I thought that's why you need a biopsy? I'm literally out of mind worrying about this :(

Thanks for your help xx