Not precisely. your immune system is weakened to certain things, like colds, during pregnancy...but it's not a symptom of pregnancy. And many women experience a stuffy nose in early pregnancy because the sudden increase in blood volume causes swelling in your sinuses...but...this can also be because of a change in the weather, etc.
I wouldn't count is as a sign, sorry! I've had a cold with all 3 of my pregnancies early in the first trimester, but it's mostly because I've been newly pregnant during cold and flu season!
Colds come out of no where..
You probably caught a virus from somewhere. Colds are not a symptom of pregnancy.
Yes and no. It's cold season here. I had cold symptoms starting almost a week before I skipped, and still have issues with runny nose and gunked-up throat. For the first week I dealt with this, I had a fever and nasty cough. That is now gone. I think I really did just start out sick with a virus. Nice little blow to the immune system. But while the runny nose thing has slowed down, it's still very much here after two weeks. That could be linked.
From my research, pregnancy can mess with your mucus membranes and sinus cavities. If you're producing a lot of goo downstairs, don't be surprised to find it elsewhere. This is why bloody noses are also common among pregnant women.
So don't take a runny nose as a sign of pregnancy. But if you're pregnant and experiencing other issues, it seems more likely that you might get one.