The Screen On My Huawei M835 Keeps Blinking?!? Help Me!

Ok, So the other day my phone randomly turns off by itself..i wasnt even touching it i just went to look at the time n noticed my phone was off. i tryed turning it back on but nothing happend..so i left it alone for a lil bit n it finnaly turned back on. except this time i wasnt getting any signal in a place that i usually do. i thought tht was odd so i turned it back off n then all of a sudden it just starting vibrating, it wouldnt even turn on or charge it just vibrated for hours, i even fell asleep hoping it would just stop and whem i woke up it was still vibrating! i tried to turn it on one more time except the screen just pops back up as if it was bever even off and the vibrating stopped. my phone is working fine now but the only thing is the screens keeps blinking in and out..it seems like its getting worse. do you know what i can do to fix it? i really dont have the money to buy a new one. help!!!!