I have always had an anxiety issue and have just recently learned how to somewhat deal with it. I find that surrounding yourself with friends and family really help. My family used to ask me about vet school ALL THE TIME, which stressed me out more because I felt as if I wasn't living up to their expectations, but I've just learned to either not respond or respond in short answers then change the subject. In time, family members just learned to stop asking because they knew that I would let them know if anything with my vet school application/journey changed or was worth mentioning.
As for studying, I would set a specific amount of time each day just for studying. I would turn my phone and laptop off (if I didn't need it) and really just try to learn the material I needed. I would also take breaks when I feel like I've really learned a subject, then go back to studying again until my "time was up". Find something that works for you. I think the most important part about studying is limiting your distractions.
Also, I know this sounds simple, but do things that make you happy EVERYDAY. Watch movies, read books, exercise, go on a walk... I find that when you are doing something that's fun and enjoyable, you tend to lose track of time (which means that you aren't wasting that time being stressed or anxious!).
Try not to think too far ahead. Your test is in September, you still have plenty of time to study and prepare yourself. Make a study plan and really try to learn the material the best you can. Take things day by day. I know this is easier said than done, but don't think about potentially failing the test again... Take that energy to motivate yourself to do things so you WON'T fail. By the time the test comes, you'll be so well prepared you'll see that all this worry was for nothing
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PS. I studied abroad in Italy for a summer during college and it was the best time of my life! I dream about going back some day.