Can I still take benadryl?

I have terrible allergies and I live where there is a ton of pollen and junk.So I have been taking two benadryl before bed every night for the past 6 months and it has helped me so much,I am no longer congested nor do I sneeze 20 times in a row anymore but I want to know if it is OK for me to take two every night or can you just take it for a few days????