Hard bumps

Kari • Married to my best friend of 7 years and high school sweet heart. So excited that we have our first baby on the way!😍
Since I've became pregnante I have been randomly getting these really hard bumps under my skin. You can't see them but you can feel them. 
They are really hard. And they do NOT roll around or move. They are stationary. I've asked friends what they could be. They said sounds like balls of fat build up or calcium build up. When I asked my doctor what they were he felt them and said he had no idea what they could be. To find out they need to do surgery and remove one and do a biopsy on it...
In 26 weeks pregnante. Over these past 26 weeks I have developed 7 hard bumps 4 on my thighs, 1 on my arm, 1 on my back. And today a new one popped up on my side just under my ribs. They don't hurt but the one on my back and the one on my side do hurt when you push on them. Does anybody know what they could possibly be???