Hey Cindy
My first suggestion to you would be to get a PH pen ASAP. Not just so you know what the PH is going in, but more so what it is comming out.
You mentioned you were growing in Miricle Grow soil mix? Mgrow starts out at a 6.0 ph range, which to me is already a tad bit to acidic. When you start adding your ferts salts will start to build up, driving your soils PH base down further making your medium even more acidic. Soon you have PH lock out which your plant will stop taking up nutes even if nutes are in the soil. Your plant will look like it wants more food so you feed it more but all that does is drive your PH lower because the plant cant absorb the food cause your PH is to low.
I would start with a soild that has a neutral PH 7.0 like a
ProMix add some perlite or grow stones. Get on a regular nute schedule and Ph your water to 6.3ish when adding nutes.
Once a week I would PH some plain water to 7.0 and water it till you can collect some run off. Once you get that run off test the PH you will notice that over the weeks the PH will start to drop because of the salt build up from the nutes. Once your 7.0 plain water ran throught you soild starts comming back in the 6.2 range add some Dolimite lime (the amount will depend on your container size). That will help buffer up the soil and keep your roots in a stable PH range of 6.3 to 6.8
Also when you collect you weekly runoff test the PPMs or EC to see how much your plants are actually eating......but I am rambling now.
You need a PH meter that you can trust and you need to know what the PH level is that your roots are sitting in. A PH meter is not an optional thing especially when you are begining.