Severe heartburn and nausea

Hey! So I'm almost 3 months pregnant and I've had the worst heartburn and nausea. Is there anything besides tums and marshmallows that will help with the heartburn? Its almost unbearable! & I wear the sickness bands every day for nausea but is there a secret trick to helping with it? Also I've heard different things..does vomiting and constant nausea usually mean a boy or a girl?? If anyone could help that would be amazing!!! Thank you💙