Where are your Trites? I would wait till your trates are over what your tester can read, do a 50% pwc
and check your parameters. This will assure the second part of your bb (the nitrifing bacteria) are strong enough. The process of nitrite to nitrate takes the longest. If after your water change your ammonia is still around 4 and you can read nitrite and nitrate levels on your tester you can pull the shrimp at that time. If ammonia is under 4 leave the shrimp in till it reaches 4. Then pull them. Check everything 24hrs later and if ammonia and Trites are 0 with lots of trates your cycled. Then its time for a big water change 75% or so to remove as much trates as possible, Under 20. Sorry for being long winded.