A little late to the discussion, but I will just add my A loose martingale is next to useless in controlling a frightened/aggressive/over-active dog, so be sure yours is fitted correctly. I personally found a harness a much better option for my leash reactive 90lb greyhound. I could hold him next to me (which helped calm him) and not worry about him injuring his neck when he leapt around like a fish on the end of the line I have the 2Hounds harness mentioned above and it worked great. Actually, I had two, but gave one away. They do have velvet, I think so they don’t rub on that fragile greyhound skin. They are somewhat adjustable, but at 11 months your girl will probably grow a bit more. If you call 2Hounds they are very helpful with choosing the size you would need. I have never needed the double leads, pretty sure I am not coordinated enough to manage but I know some people who have.
All that said, it sounds like a properly fitted martingale might be all you need for now.