At 6 months of age, an "infant" hits developmental milestones... and becomes more "alert" and physical and cognitive abilities increase. THIS is why, often times, that at 6 months of age you will see that many babies have a change in sleep patterns. It's something that happened to both my children as well. It passes. Of course you do want to have a bedtime "routine" in place, which works for you and baby. If nothing else is wrong with your baby and no illness or health issues or gas or teething problems or separation anxiety issues or growth spurts... then I would chalk it up to it being a developmental phase. My Pediatrician said she sees this all the time at this age. Again, their sleep patterns will always change as they develop and grow physically and cognitively. Sleep patterns are not static, nor for adults either.
Sometimes, not swooping in right away, and letting them soothe themselves back to calmness or sleep can help them learn this ability. But there are many sleep "methods." You have to go according to what is best for you and what you believe in and what is best for your and baby's comfort. For me, my 1 yr. old boy can often soothe himself back to sleep.. .but if he does not and cries at a certain "pitch"...then I know I need to go in there and check it out. At this age, I know he has night-terrors and nightmares. I can tell by his face and the pitch of his cry/behavior. Every child is different... and at each age. Sometimes they just want a snuggle. Often times, I will just sing to my boy (it's the same exact song each time).. .and that is enough to calm him and get him back to sleep. This is the "routine" I have done with him since birth... and now, it is like a "light-switch." When I start to sing, he will become calmer/quieter and he knows it's time for sleep. Also, he has a stuffed cow that he sleeps with since the time he was 6 months old and this helps him to sleep too.
Try different things. It will all work out in the end.
Good luck,
~Susan
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