Are lab run blood or urine tests for amino acid profiles useful to find deficiencies in a vegan diet

30M, 6'5 at 210lbs. Hello! I'm currently in my third year on a vegan diet for ethical reasons. I try to keep my diet balanced and I quarterly have my blood checked for deficiencies in Omega-3 and the vitamins B12 and D3. So far, I don't have any issues, deficiencies or feel a negative impact. However, one thing I'm not sure about is my protein intake. I eat a lot of protein and try to keep a balanced mix between legumes, tofu, TVP, nuts and seitan, but since I avoid meat and whey, I don't know if this is enough to keep all amino acids balanced as well (or at least the 9 essential ones) I found a lot of at-home tests starting at $20, but those feel more like random number generators than actual trustworthy results. I also found another lab relatively close that offers blood and urine tests to create a profile of all 20 amino acids, but I still don't know how significant those results are. Like do those values constantly change depending on the time of the day or if you ate recently? Are those tests even useful to spot deficiencies from diet or are they just used to spot real disorders like Maple syrup urine disease? I tried googling all of that, but quickly realized I'm not qualified enough and lack the formal education to find results that are useful and not just marketing for at-home tests that don't seem trustworthy at all, and I'm better off asking a professional. Thanks in advance!