Feeling cervix

So today I was having on and off period type cramping, sharp pains in my cervix and back pain every 5 min for a few hours.. it slowed down and I’m only getting a few small cramps in an hour now, I waited to call my doctor to see if it went away and it kinda has, but my friend told me she used to check her own cervix so I decided to try it (I washed my hands first and it is safe according to many sites so no annoying comments about infection) and I had to go in very deep but once I did I’m assuming I felt what is my cervix but my whole finger tip went in there.. no idea if it really was my cervix but don’t think it could really be anything else, but from feeling it, I would say it’s atleast 2cm since my finger went in the hole very easily. Now I’m thinking I might want to call my doctor? Advice please! I’m 33 weeks!