Introducing solids!

Julieta
Hi, my baby is a little over 6 months and we just started with solids. She was EBF but we've always had a hard time feeding her. I feel like she's just not interested plus she hates the bottle so she drinks the minimum to go by through the day while I'm at work. The thing is, the only way she swallows the oatmeal or the purée is by sucking her thumb and I'm not sure if she doesn't know how to swallow or its just stressful for her so she's trying to sooth herself. I'm concern because she's not gaining weight but I don't know what else to do to get her to eat. Have any of you had a hard time introducing solids?? Please help!!