Can I get some help plz ....

I'm 22 weeks 2 days pregnant, I've been seeing my dr since I found out but it's just like everytime I go to an appointment she always says a test didn't come back normal and I have to give blood again then the test come back and everything is fine , I mean I don't mind but it kind of aggravates me ' and she's always rough for my first ultrasound she rushed threw it I know I wasn't that far along but I didn't think it would go so fast when I go in for my appointments since then for the heart beat checks ect . She press this thing so hard down it hurts I say something and she ignores it (I'm on the bigger side) idk if that's the reason but I'm not liking it , so on to the next thing my sister was seeing her partner when she was pregnant and they told her what she was having there , but when it came to me she sent me to a specialist but my question is , is it okay for me to switch to another dr being that I'm 6 months ? 
Thanks in advance