This is probably a dumb question......

Katie • 25 years old. Me and my fiancé have a almost 3 year old and TTC #2!!
I am 18w2d. As I am sitting here on my couch I am feeling this stabbing pain in my upper abdominal area. I know I have had rib cartilage problems in the past. But idk what this is. I feel it more so when I breath. It's starting to really sorry me. Obviously it's Saturday and my doctor is closed.