Excessive gas, burping and hard bloated stomach in 5yr old

Hayle • 5 yr old daughter. 1 👼🏼 1-23-19. Ttc baby #2.

So I know something is wrong with my 5 yr old. My poor girl for about 4 weeks has been passing a lot I mean a lot of gas. Starting Christmas <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">Eve</a> her belly is bloated and hard. She’s burping along with her gas and her poops are changing between constipation and diarrhea. I guess she didn’t gain weight either since her 4 yr old check up, but eats normal. I thought she was lactose but she hasn’t had milk since we took her in and she’s still the same. Last night she came running into our room saying her stomach hurt and sounded like she was going to puke and she let out the loudest longest burp. Said she felt better and her stomach went back to normal.Her doctor made us get her blood work to check for celiac disease and stuff. But I won’t know until Thursday 🙄 I just feel bad that she can’t eat anything without getting like this for another almost 5 days. Anyone have a child that had the same issues? What did it end up being?