my labrador pupoy seems to have gotten aroused

Question
i have a 7 month old labrador puppy..Uptil a week or so he was an obedient little boy...he spends most of his time with my mother so 90% of the times hed listen to what shed say...he was also a quite dog and we never saw him barking at anybody or crying....and lastly after we engaged a dog trainer hed walk and heel also perfectly...however of late his behavior seems to have gone for a toss...he doesn't listen to anybody...his penis is alsmost always out...he seems restless and fidgety ...even while walking he acts like a mad dog pulling on the leash vehemently...also if he is left alone for even a short time he starts crying and whelping...and lastly so far he never went near my grandmother who is aged and bed ridden...however of late he seems to make it a point to jump on her bed..hes also leg humping a few people in the  house...is this normal behaviour??? what is the cause??? and will my dog ever return to his obedient state? also please tell me if you have encoutered such behaviour before

Answer
This is the age where they TEST their humans.  Think of a bratty 2 year old child.  This is the equivalent time for puppies.  You will need to be extra vigilant with him to show him that you are STILL running the house.  You will need to go back to step one and treat him like a puppy you just brought home.  When he does bad things, you will need to correct him right away to show him that you are in charge.  He's growing up, his hormones are flowing through his body, and he's trying to become the Alpha dog in the house.  This is absolutely NORMAL for this age.  Just be consistent in your routine and how you correct his mistakes and he'll make it through just fine.