Unfortunately getting tested for ASD is really difficult. I recommend seeing someone before you turn 18, you will be a higher priority since you'll likely be going onto higher education.
I recommend taking the autism quotient test
It's pretty much the same one they gave me (i had the screening test in late may, getting tested fully this year hopefully), though I have not had a good time trying to get assessed. CAMHs were useless (always are), Dr had no authority to request a referal. I ended up getting a test by pure luck, I told my gender psychiatrist (i have dysphoria) that I was concerned about this, and said my results on the autism quotient are 38-41 usually. and he talked to his psychiatrist colleague who got me an appointment in august, on condition I score high enough of the screening test. I got 41/50, like I said i would
Prepare to be ignored or fobbed off. It's very frustrating and upsetting, especially if you're an anxious person, but you gotta stand ur ground and look out for #1 (you.). That's just the state of mental healthcare here. Luckily the psychiatrists are good, it's the middle men (CAMHs or doctors who act like arm chair psychiatrists, who say 'oh you dont have autism, it's just _.'. They have 0 authority to diagnose or dismiss the possibility of one.), that can be irritating. PLEASE try get tested anyway, if you do have ASD you need to know. Try to rally some allies. Don't be beat down if you dont get far your first time! In the mean time, check out resources like subreddits, facebook groups, videos.