The brewer diet is not for everyone--the ideas are sound, but the amt of protein suggested is too high for some mamas. If you can do a urine test for protein (making sure you are well-hydrated before peeing, and that you clean off your yoni first, to get a 'clean catch'), that may help you decide. A trace of protein in the urine is normal for most pregnant women. +1 or more protein in the urine can mean that you are not eating enough protein and may benefit by increasing your protein intake.
Protein in the urine can indicate protein deficiency that is leading to poor performance by your kidneys (and poor state of the liver as well, but that is tested via blood tests not urine). This is unlike glucose in urine, which indicates *too much* sugar in your system that your kidneys are helping you to get rid of. Your kidneys are not supposed to 'help you get rid of' protein. The appearance of protein in the urine indicates that the kidneys are not properly doing their nutrient-recycling job--which is one of many tasks the kidneys are responsible for, along with production of the hormones renin and angiotensin that help you modulate blood pressure appropriately.
Some swelling of lower extremities is normal for many pregnant women. Even the hands, depending on various circumstances of your life. Swelling should reduce noticeably, if not completely disappear, after sleep, and the fact that it doesn't do so is a cautionary sign for me. Yes, heat and humidity can make a difference in the amount of reduction of swelling overnight--but you should still see *some* difference. Drinking more fluids, and salting to taste are important in maintaining proper osmosis and other circulatory/blood factors that help your fluids stay in your bloodstream rather than leaking out.
Exercise is also important--at least some gentle exercise, 3-5times a week for at least 20-30 minutes--to maintain healthy circulation/oxygenation and keep all of your systems running well. Swimming is especially good for swelling as the hydrostatic pressure is added to the muscular activity in helping force fluids up from the feet/ankles and back into circulation. Again, doesn't have to be too vigorous for your fitness level right now--but continuous for a time.
If you really are working up to pre-eclampsia, then it is important to learn more, and watch all of your signs more carefully for a time while you figure it out. Your blood pressure may rise or may not, not all women w/pre-e experience a significant b/p elevation, or at least not until very late in the game, and suddenly (a rise of diastolic--the lower number--of 15 or more points from your usual). Yes, some women experience pre-eclampsia as a result of inadequate protein intake. If you do test and find protein in your urine, then increasing your protein should show a noticeable change in your urine test within a week or so. However, research on pre-e suggests that there are many possible root causes for it--most of them dietary: deficiencies of calcium, omega3 fatty acids, the 'anti-oxidant' vitamins. It is also true for some women that excessive life stress can lead to sufficient physiological strain to bring on pre-e--once your b/p rises as a result of stress, for instance, you may no longer be adequately circulating oxygen/nutrients to yourself or baby, leading to other system breakdown and the group of symptoms we call 'pre-eclamspsia'. It is just as problematic either way, though! While you're considering diet and exercise, don't forget to include a review of life-stressors and whether or not you are managing stress well enough.
So, seems like a good time to learn more, do a diet review, take on more exercise if you don't already--take a pro-active approach to wholeness/welness for yourself and baby.