Phoning and texting

Two main problems on my Wildfire: 

When I'm talking to someone, very often I find that I get disconnected and when I look at the screen, I find I'm actually ringing one of my other contacts.  I am very careful not to touch any buttons, so it's nothing I am doing.

Secondly, Sometimes when I text, my messages go elsewhere and when I check my sent messages, I haven't made a mistake, they are still going to the person I intended, not only do they go to contacts, they go to contacts that I have deleted and are nowhere in my phone.

Can anyone help please.