My phone was flat so plugged it to charger for a few hours, return to turn it all back on-but it didn't switch back on. Pulled out the battery & my sim,phone still didn't turn on,then tested my battery in my friends phone as she as the same phone. Battery worked fine in her phone. Would my phone be in some kind of recovery mode or safe mode?? If so how would one get it back to normal mode??

Help will be much appreciaed