At this point I wouldn't be thinking of hunting until you have a lot more control, you'll be a danger to yourself & everyone around you.
What have you been riding up until now? I ask because I'm wondering if you've just got a lot more horse & energy under you than before & that makes you feel like you're being run off with - a big horse stride can feel very onward if you aren't used to it & they often need more stopping distance too. If you can't get your RI to teach you in a field so she can see the problem can you get her to take her for a canter & see what she thinks?
Bits can be a minefield & what works seems to depend on the horse. Jim, my ID, was better in a Pelham with two reins since it meant I only used the curb as & when it was needed, on a single rein it was too restrictive for his liking. Better still though was a full cheek myler mullen mouth because he was much more likely to keep the contact, yes he could occasionally get strong in it but that was far better than ducking behind the contact & leaving me with nothing. But ultimately nothing would work if he decided to go, and his solution to feeling it might was to buck until I came off - believe me no-one was going to sit the strings of bucks & launches he could throw, he was the only horse I saw buck stirrup leathers off the saddle after I came off! Sometimes you accept some horses are not suitable for some jobs & no amount of tack or schooling will change that.
I'd start with a RI or very good rider's assessment & go from there. Seeing & feeling can give a very different perspective.