i can tell you a counteract mechanism for your counting and checking/rechecking OCD if you practice it properly,you can get rid of that OCD ritual

remember this " OCD is a slow burning fire, OCD rituals are gasoline.when you do more rituals there is more fire"
counting and checking is a form of OCD ritual when you perform it gives you a temporary relief but actually it's grow your OCD
you cant suddenly stop you OCD rituals but setp by step

1) open an google mail account and create a google sheet (an OCD Diary) only for your OCD relared things ( so privacy and confidential only to your self)

2) end of every day mark how many OCD rituals did you make
( ex how many time counting ,how many had wash )

if give you a graphical view about your OCD

lest say you're doing counting OCD five times per day. now just give up one counting ritual
for a week and dayly mark it on your sheet and put a note

" i did'not count or did this OCD ritual and no bad happen this particular day"

2 week give up 2 counting/checking/rechecking/washing etc ritual and mark it on your sheet

and 3 rd week so on
so you can view how you OCD level reduced than past