Dignosed bipolar/mood disorder and schizoaffective mabey need a med adjustment?

i am on 900mg of lithium a day 1 capsul in the am and then 2 at bed and also i am on 2mg of rispiridole and thats in the pm, now i was off my meds for about 3 weeks and have been back on them for a month now, but for about a week now i havnt been able to shake this feeling of hopelessness, overloaded and i feel like theres nothing i can do about , ive been really bitchy more then normal, and for somereason out of no where i will get this sudden urge to want to do harm to one of my 3 kids. i dont want to bejudged for that i have a saftey plan in place and when that pops in my head i let my mom know go to my room lock myself in and dont come out till im stable again but i wanted to know if my dosege might need to be up'd because i been on these med for about a year now and up untill about a week ago i hadnt had any of these visions, other then when i was off the meds for those 3 weeks of hell, anyways??