I can't say words that start on R like router but have no issues with words ending on R like fear. What should I do?

I can't say words that start on R like router but have no issues with words ending on R like fear. What should I do? I talked with my family earlier today about some issues with our internet, and when I tried to say that the issue is the router i just couldn't say the word (router). I feelt something in my stomach and my pulse increased as I tried to say router. The word just didn't come out of my mouth so I had an awkward pause and said internet box instead. I have no issues when talking otherwise and I never stutter(repeat letters). But when there's a word starting on R I just get quiet and try to change it for something else. It's gotten worse with time. First it was just some words, but now it's every word starting on R and it's gotten to the point where it's affecting my ability to communicate. What can I do? I'm not sure if it's a stuttering issue or some other speech impediment, but I can say long sentences without getting stuck as long as there's no words starting on R. Words ending on R and words with R in the middle is no issue either. When I'm alone like when taking a shower I can make the rrr sound and say r words quietly, but when talking with someone I can't.