Sorry to hear about this concenr for Marva Cox.
Absolutely, this is well worth a vet visit without delay. At 20 years of age, her overall health condition can change easily from day to day. If a basic blood test and urine test has not been conducted in the past 6 months, that is your priority. You must rule-out problems including hyperthyroidism,which can result in blood pressure issues, heart problems, blood clots, etc...Also, kidney disease, and esepcially diabetes, are considerations with they symptoms you are describing.
Without the basic testing, there is no way to know what systemic (internal) issue may b going on and if it can be medical managed.
Otherwise, we have no way to improve her overall condition at home.
Definitely, strong vote for a vet visit today and som basic laboratory tests.
Hope that information helps