You're not alone. I'm a massive hypochondriac too, and having read all the possible symptoms of all the bad things that can happen from my anti-androgens and Estrogen, I've been convinced I've had nearly every symptom at some point.
I follow a ton of trans women online, and the single case of DVT I've heard of, is from one woman who was taking herbal HRT ( Natural does NOT equal safe ), and then doubled the recommended dose, then doubled it again.
I know one trans woman who was self medicating, and when she had her first blood test she found her blood Estrogen level was massively over female levels. Yet despite this, no DVT. I still would not recommend doing what she did though. She's corrected her levels now.
As far as I've read, patches are one of the safer ways to take Estrogen, because it bypasses the liver.
Having said all that, I'm not a doctor, these are just my experiences, things I've heard and read. So listen to your doctors before you listen to random people on the internet like me