You've gotten some good advice. Here's what you need to do:
1. File immediately in your local court. As for an order that the child not be removed from your state while the case is pending.
2. You will request joint legal custody. There is no reason not to have that.
3. You COULD request primary physical custody, but as you've been told, the court probably won't award that because of your job. So if you really want primary physical custody, you'll need a different job (even then, you might not get it - because the court will consider the fact that Mom has been the primary caregiver). Therefore, my view is that you're probably better asking for shared physical custody with Mom having the child most of the time and you having an extended time in the summer, alternating holidays, and spring or fall break at school (when the child is old enough to be in school). Your attorney can guide you here.
4. Ask for the court to order Mom to pay 100% of the costs of transportation for you to see the child.
5. Ask for temporary visitation orders granting you visitation.
It's difficult now (and almost always is during the early stages of a divorce), but your biggest problem is your schedule. It is always recommended that people get rigid court orders for visitation schedules, but a rigid order may conflict with your work schedule. So let's explore that a little bit:
- How far ahead do you know when you'll be away?
- How long are you gone each time?
- How long do you stay in town when you are not driving?
- Do you have access to the Internet when you're away from home?
Depending on the answers to the above questions, it might be possible to come up with a schedule that allows you to see your child when you're back in town but which is also an enforceable order.
And I agree with the other advice. Relax. You will get to spend time with your son. Ultimately, your relationship with your son will be heavily influenced by Mom, so you want to be careful not to over-react. You will have to bite your tongue sometimes and keep things in that you'd like to say. You will have to deal with her being unfair in just taking off and preventing you from seeing your son. But in the end, your child benefits if you can find a way to work out a civil co-parenting relationship.