Problems sending texts and connecting to 3G after 6.0.2 update

Since updating to 6.0.2 my iPhone 5 is having problems sending texts (often - but not always - says texts weren't sent and must hit "retry" a couple times) and having problems connecting to 3G even in zones with good coverage. In general it's much slower than before the update when connecting to 3G. I don't know if this is due to Sprint or due to the update? Yes, I have turned it on and off many times and reset my settings, but it hasn't helped. Anybody else experience this problem?