Does this set have a unique minimal element?

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Suppose some ordering $\succ$ of the positive integers $\{n\in\mathbb{N_{>0}}\}$, satisfies:

Transitivity:

$a\succ b \land b\succ c \implies a\succ c$,

$\succ$ generates a measure of equality $\dot{=}$ not necessarily corresponding with $=\quad$:

$a\dot{=}b\iff a\succ b \land b\succ a$

Reflexivity:

$n \succ n \lor n \dot{=} n \quad \forall n \in \mathbb{N_{>0}}$

$n \succ n \lor n=n \quad \forall n \in \mathbb{N_{>0}}$

Antisymmetry:

$(a\succ b\lor a\dot{=}b) \land (b\succ a\lor b\dot{=}a) \implies a\dot{=}b$

Every element has a successor:

$\forall n\in\mathbb{N_{>0}} \quad\exists\quad m: m\succ n$

Every element has a unique immediate predecessor:

$\forall n\in\mathbb{N_{>0}} \quad\exists m:(n\succ m \quad \land \quad \nexists p:(n\succ p\succ m\land p\dot{\neq}n\land p\dot{\neq}m ))$

Every totally ordered subset of $\mathbb{N_{>0}}$ contains at least one minimal element:

$Q=\{q:(n\succ q \quad \forall n\dot{\neq} q)\}$. $Q\neq\emptyset$

^ I struggled to write this; help me out if you can.

Can you show that there is only one set of elements satisfying $a\dot{=}b\dot{=}\ldots$ ?