i have an issue when i go to play minecraft with mods (forge) it wont let me get in a game and or if it does it superrrr lagy and crashes tell i rage

i hope this does not hurt your feeling its just my friends are screaming at me GO REPORT THE ISSUE SO MOJANG CAN FIX IT. witch that is what im doing right know, my minecraft username is littlekitty647. Bye!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 😛