Low blood pressure

So I just took my blood pressure and it was 120/76 which is considered a little low? I’m 29 weeks pregnant as well. My doctor said there’s nothing they can really do that’s just what happens in pregnancy. I’m concerned because everything I read says it drops in 2nd trimester and I’m in my 3rd trimester. I’ve been dizzy for 2 days now and I’m starting to worry. What foods can I eat or what can I do to boost it just a little? I don’t want it to get to low