1 bed bug. a problem?

ok so yesterday i woke up with 4 bumps on my arm which i thought were mosquito bites but then they were raised higher than mozzie bites and looked a little more red. i decided it wasnt anything to worry abt and then i saw an bed bug crawling on my WHITE bed sheet. u can imagine my horror! i managed to smash it in a tissue and the stuff that came out was brown not red. i looked around the bed for more bgs but cant seem to find any. i've slept on the bed 2 times since then and i've had no new bites. is it possible that it's only 1 bed bug that was present and i killed it?

i'm not very rich and really can't afford to get exterminators plus my room is really cluttered and it's going to be a nightmare to clean EVERYTHING. Please don't reply with scary answers. I hated sleeping on the bed the last 2 times ( an afternoon nap and one over night) but since nothing has showed up on my bed or on my skin…. is it safe to assume that it was just one bug? i feel itchy just thinking abt them.

also… anyone with any cheap solution to clear them out? my dad suggesting putting garlic arond the edges of the bed. i don't knw abt u but i'm not sure abt how i'de feel sleeping in a bed smelling like garlic. my boyfren doesnt seem to care so this is up to me to solve. does diluted dettol spred arnd the edges of the bed work?? pls help guys…