having another nonsense problem

just less than a week and i will complete one month of taking muay thai sessions. but my problem is, im losing weight. this i do not approve. ive lost 10 pounds by combining my weekday jog and muay thai on the weekend. i guess im going to be the subject of envy by some since im the type who can easily lose weight (almost effortless). but on my end, its as annoying as having difficulties in losing weight because i have difficulties gaining weight. now, i gained weight because i eat six meals a day. (three full meals and three moderate to heavy snacks). since i started exercising, the six meals are now inadequate. so i have to eat more. it wont be much of a problem if food wasnt expensive! now that i have to eat more, i need to spend more (or maybe try to learn how to cook but at the moment, i have no interest). i try not to spend more than P100 a day on weekdays given my "just enough" monthly salary (and i go nuts on food during the weekend whenever i go to the mall). the affordable yet tasty meals i can think of are one to two jeepney rides away (and thats just a one-way commute).so my problem is, how do i gain weight, without spending a lot and at the same time, allowing me to increase my current physical activities (because im aiming to have a twice weekly muay thai session, retain my thrice weekly jog and maybe an extra day for a regular gym. im thinking i should have been an athlete if i didnt prevent myself from engaging in sports and allowing my laziness to grow when i was in high school).

right now, my shins hurt like hell. not sure if its because of the muay thai session last saturday or i over exerted myself yesterday. it could be both. im not used to doing round house kicks or hitting my shins against a punching bag. but the thing is, my shins didnt hurt as much the two weeks prior to my last saturday session. then yesterday, i thought of pushing myself further on my regular jog. so even if my body was a bit sore due to the muay thai session the day before, i jogged/run until my legs wobbled due to tiredness. at least my knees dont hurt no more. so when i attempted to repeat what i did yesterday, halfway through the jog, my shins started to feel like its shouting expletives at me (the same way my knee did a few months ago). so i had to stop because i was really having a hard time running and could only walk really slow. had to ride a jeepney home. so either i overexerted myself or its time to buy a new pair of running shoes. i think the former. im still a month away from completing my thrice weekly jog for three months. im just going to rest tomorrow since i cant risk injuring myself because i have a hearing in malolos, bulacan on wednesday morning.