Sorry you had a bad consultant experience.
I am to an extent where you are, but further along.
I am currently 27 weeks, have a high BMI and pre-existing high blood pressure, so was already medicated before becoming pregnant.
Firstly, on BMI the recommendation is not to lose weight whilst pregnant. It is recommended to not gain as much (I think for me it is up to 11kg/20lb) and you may find that you do not (I am bordering 7 months and have gained just under 4lb). The most important things are to eat a healthy balanced diet and to build in some exercise to keep you healthy in pregnancy (they may mention Slimming World to you as that is the only weight loss program I believe that is endorsed by the Royal College of Midwives). As part of that you may find you lose weight, but it is from healthy choices rather than actually dieting. It is very important to make sure that you have a balanced diet where you can to make sure that baby gets all the nutrients it needs and dieting and cutting out will not help that.
Sorry about the morning sickness and I can't really help with that as I was lucky and skipped it completely. In the early days it is eating what you can stomach sometimes and maybe add in a pregnancy vitamin. By this stage, my stomach is feeling squashed so I can't eat as much anyway.
As for your blood pressure, it is always great fun. I am surprised you saw a consultant so early (I was nearly 20 weeks at my first appointment). If they have increased your medication, I think it depends by how much. Mine did and the GP have still not updated my prescription, but it was only by an extra pill so just means I run out a couple of days early. Best thing is to give the surgery a call and let them know. The GP may be able to sort it and check it with the consultant or they may ask for you to see the GP to check.
You will eventually get more blood pressure checks as you go along. They were not overly bothered before 20 weeks (although mine was already up rather than a sudden increase in pregnancy), but after that I have my regular midwife appointments, have been told to get BP checked in between if I feel like it has gone up (they may tell you to do it every so many weeks as by now I know whereas if it is new to you you may not recognise the signs) and I will have further consultant appointments later on. You should also be booked in later on by the midwife for growth scans which here start from 28 weeks depending on risk but may change by area (high blood pressure puts you in high risk).
Hope that helps and if you have any questions just say. As hard as it is, try to relax when you can as that can help lower blood pressure and the important thing for you is to keep your blood pressure under control to keep baby safe.