Thanks for the kind words, bro. I'm glad to have the Q/A as well as Next Level Nutritional Services. Sharing my experience is rewarding and hopefully, it's getting a lot of guys big/ripped, while staying healthy. As for your question, my first thought is also hematocrit, but without labs, it's only a guess. If this is the case, donating a pint of blood will fix the problem. If this is the problem, you're putting a lot of unneeded stress on your heart, bro. I would suggest donating a pint of blood every several months, especially if you are using TRT year round. Also, if you have problems with clonidine, I would find a new drug that doesn't give you side effects. I find that norvasc works well for me and the side effects are minimal. For a lot of BP meds, the sides get easier to deal with, once you are used to taking it regularly. 138/90 isn't awful but it isn't great either. I walk around in the off season at 110/70. You can do better! Your kidneys will thank you.
Since you're going into the Dr, if you have insurance, I would just opt for a complete physical. Some providers will flip the bill for everything for a yearly physical. You're Dr will check everything along with your hematocrit and kidney function, which is my other concern for you. Since you are a long term user, I would also get an EKG to check for heart enlargement. Not all heart enlargement is a bad thing. The heart is a muscle that can develop when exercised. Most serious athletes will have some heart enlargement. The key is to keep an eye on it and watch to see it's development over time.
Sorry I do not have a more specific answer for you. This one is going to take some labs. I'm sure you will be fine, but you do need to know exactly what is going on in your body.